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EASTERLY ACQUISITION CORP.
205 Hudson Street, 7 ^th  Floor
New York, New York 10013

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
To Be Held at 10:00 a.m. Eastern time on [                ], [                ], 2018

TO THE STOCKHOLDERS OF EASTERLY ACQUISITION CORP.:

        NOTICE IS HEREBY GIVEN that a special meeting of stockholders (the " special meeting ") of Easterly Acquisition Corp., a Delaware corporation (" Easterly "), will be held at 10:00 a.m. Eastern time on [                        ], [                        ], 2018, at [                        ], or at such other time, on such other date and at such other place to which the meeting may be adjourned or postponed.

        You are cordially invited to attend the Easterly special meeting to vote on the following proposals:

        (a)    Proposal No. 1—The Merger Proposal —to consider and vote upon a proposal to approve and adopt the Agreement and Plan of Merger, dated as of June 23, 2018 (as amended pursuant to the First Amendment to Agreement and Plan of Merger and Sponsor Letter, dated as of August 29, 2018 (the " Amendment "), and as it may be further amended from time to time, the " Merger Agreement "), by and among Easterly, Sirius International Insurance Group, Ltd. (" Sirius Group ") and Sirius Acquisitions Holding Company III, a wholly owned subsidiary of Sirius Group (" Merger Sub "), and the transactions contemplated by the Merger Agreement, including the merger of Merger Sub with and into Easterly with Easterly surviving the merger as a wholly owned subsidiary of Sirius Group (the " Merger ").

        (b)    Proposal No. 2—The Adjournment Proposal —to consider and vote upon a proposal to adjourn the Easterly special meeting to a later date or dates, if necessary, to permit further solicitation of proxies if, based upon the tabulated vote at the time of the Easterly special meeting, there are not sufficient votes to approve one or more proposals presented to Easterly's stockholders for vote at such special meeting.

        These proposals are described further in the accompanying proxy statement/prospectus. Only holders of record of Easterly common stock at the close of business on [                        ], 2018, the record date for the special meeting, are entitled to notice of the special meeting and to vote at the special meeting and any adjournments or postponements thereof. A complete list of Easterly stockholders of record entitled to vote at the special meeting will be available for ten days before the special meeting at Easterly's principal executive offices for inspection by stockholders during ordinary business hours for any purpose germane to the special meeting.

        Easterly stockholders are being provided the accompanying proxy statement/prospectus and proxy card in connection with the solicitation of proxies to be voted at the special meeting and at any adjournments or postponements thereof. Whether or not you plan to attend the special meeting, you are urged to read the accompanying proxy statement/prospectus carefully and submit your proxy as directed herein. Please pay particular attention to the section entitled " Risk Factors " beginning on page 41.

         After careful consideration, Easterly's board of directors has approved and adopted the Merger Agreement and recommends that Easterly's stockholders vote "FOR" the Merger Proposal and the Adjournment Proposal. When you consider the board recommendation of these proposals, you should keep in mind that Easterly's directors and officers have interests in the Merger that may conflict with your interests as a stockholder. See the section entitled " Proposal No. 1—The Merger Proposal—Certain Interests of Easterly's Directors and Officers and Others in the Merger ."

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        If you have any questions or need assistance voting your shares, please call Easterly's proxy solicitor, Morrow Sodali LLC, at (800) 662-5200 (banks and brokers call collect at (203) 658-9400).

         Your vote is very important. If you are a registered stockholder, please submit your proxy to have your shares voted as soon as possible by completing, signing, dating and returning the enclosed proxy card in the postage-paid envelope provided. If you hold your shares in "street name" through a bank, broker or other nominee, you will need to follow the instructions provided to you by your bank, broker or other nominee to ensure that your shares are represented and voted at the Easterly special meeting. The transactions contemplated by the Merger Agreement will be consummated only if the Merger Proposal is approved at the Easterly special meeting. The Merger Proposal is not conditioned on the approval of the Adjournment Proposal and the Adjournment Proposal is not conditioned on the approval of the Merger Proposal.

        If you fail to return your proxy card, and do not attend the special meeting in person, if you abstain from voting or if you hold your shares in "street name" and fail to instruct your bank, broker or other nominee how to vote, the effect will be that your shares will not be counted for purposes of determining whether a quorum is present at the Easterly special meeting and, if a quorum is present, will have same effect as a vote "AGAINST" the Merger Proposal but no effect on the vote for the Adjournment Proposal. If you are a stockholder of record and you attend the Easterly special meeting and wish to vote in person, you may vote in person, which will have the effect of revoking your proxy.

         Pursuant to Easterly's amended and restated certificate of incorporation, as amended (" Easterly's charter "), Easterly public stockholders may redeem shares of Easterly common stock for cash upon the closing of the Merger. The redemption amount would equal the pro rata share of the aggregate amount on deposit (as of two business days prior to the closing of the Merger) in the trust account (the " Trust Account ") that holds the proceeds (less taxes payable and any interest that Easterly may withdraw to pay taxes) of Easterly's initial public offering (the " IPO ") that closed on August 4, 2015. For illustrative purposes, based on funds in the Trust Account of approximately $148.0 million on August 31, 2018, the estimated per share redemption price would have been $10.41 per share. There is no specified maximum redemption threshold under Easterly's charter. In no event, however, will Easterly redeem public shares in an amount that would cause its net tangible assets to be less than $5,000,001.

         EASTERLY PUBLIC STOCKHOLDERS MAY ELECT TO REDEEM THEIR SHARES EVEN IF THEY VOTE FOR THE MERGER PROPOSAL.

         TO EXERCISE YOUR REDEMPTION RIGHTS, YOU MUST (I) IF YOU HOLD EASTERLY UNITS, ELECT TO SEPARATE YOUR EASTERLY UNITS INTO THE UNDERLYING PUBLIC SHARES AND PUBLIC WARRANTS PRIOR TO EXERCISING YOUR REDEMPTION RIGHTS WITH RESPECT TO THE PUBLIC SHARES, (II) SUBMIT A WRITTEN REQUEST TO EASTERLY'S TRANSFER AGENT TO REDEEM YOUR EASTERLY PUBLIC SHARES FOR CASH, AND (III) DELIVER YOUR PUBLIC SHARES TO EASTERLY'S TRANSFER AGENT, PHYSICALLY OR ELECTRONICALLY USING DEPOSITORY TRUST COMPANY'S DWAC (DEPOSIT WITHDRAWAL AT CUSTODIAN) SYSTEM, IN EACH CASE IN ACCORDANCE WITH THE PROCEDURES AND DEADLINES DESCRIBED IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS. IF THE MERGER IS NOT CONSUMMATED, THEN THE EASTERLY PUBLIC SHARES WILL NOT BE REDEEMED FOR CASH. IF YOU HOLD THE SHARES IN STREET NAME, YOU WILL NEED TO INSTRUCT THE ACCOUNT EXECUTIVE AT YOUR BANK, BROKER OR OTHER NOMINEE TO WITHDRAW THE SHARES FROM YOUR ACCOUNT IN ORDER TO EXERCISE YOUR REDEMPTION RIGHTS. SEE " PROPOSAL NO. 1—THE MERGER PROPOSAL—REDEMPTION RIGHTS " IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS FOR MORE SPECIFIC INSTRUCTIONS.

        An Easterly public stockholder, together with any of his, her or its affiliates or any other person with whom he, she or it is acting in concert or as a "group" (as defined under Section 13(d)(3) of the Securities Exchange Act of 1934, as amended), will be restricted from redeeming in the aggregate his, her or its shares or, if part of such a group, the group's shares, in excess of 15% of public shares of Easterly common stock. Holders of Easterly outstanding public warrants and units do not have

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redemption rights in connection with the Merger. Holders of outstanding units must separate the underlying public shares and public warrants prior to exercising redemption rights with respect to the public shares. The holders of shares of Easterly common stock issued prior to the IPO, which are referred to as " Founder Shares ," have agreed to waive their redemption rights with respect to any shares of Easterly capital stock they may hold in connection with the consummation of the Merger, and the Founder Shares will be excluded from the pro rata calculation used to determine the per-share redemption price. Currently, Easterly's stockholders, which includes Easterly Acquisition Sponsor, LLC (the " Sponsor "), and Easterly's original independent directors and their permitted transferees, collectively own 25.8% of Easterly's issued and outstanding shares of common stock, including all of the Founder Shares. The Sponsor and Easterly's original independent directors have agreed to vote in favor of the proposals presented at the special meeting.

        On behalf of the Easterly board of directors, we thank you for your support and look forward to the successful completion of the Merger.

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ABOUT THIS PROXY STATEMENT/PROSPECTUS

        This document, which forms part of a registration statement on Form S-4 filed with the U.S. Securities and Exchange Commission by Sirius Group, constitutes a prospectus of Sirius Group under Section 5 of the U.S. Securities Act of 1933, as amended, with respect to the Sirius Group securities to be issued to Easterly security holders if the Merger is consummated. This document also constitutes a notice of meeting and a proxy statement under Section 14(a) of the U.S. Securities Exchange Act of 1934, as amended, with respect to the special meeting of Easterly stockholders, at which Easterly stockholders will be asked to consider and vote upon a proposal to approve and adopt the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, among other matters.

QUESTIONS AND ANSWERS ABOUT THE MERGER, THE SPECIAL MEETING AND RELATED MATTERS

         The following questions and answers briefly address some commonly asked questions about the proposals to be presented at the Easterly special meeting, including with respect to the proposed Merger. The following questions and answers do not include all the information that is important to Easterly stockholders. Stockholders are urged to read carefully this entire proxy statement/prospectus, including the Annexes and the other documents referred to herein. See the section entitled "Where You Can Find More Information" beginning on page 350. The following questions and answers do not include all the information that may be important to you as an Easterly stockholder.

About the Merger

Q:

Why am I receiving this proxy statement/prospectus?

A:

Sirius Group, Easterly and Merger Sub entered into a Merger Agreement on June 23, 2018, providing for a Merger of Easterly and Sirius Group, whereby Merger Sub will be merged with and into Easterly, with Easterly surviving the merger as a wholly owned subsidiary of Sirius Group. Easterly common stock will be exchanged for Sirius Group common shares and the public warrants will become warrants to acquire Sirius Group common shares. A copy of the Merger Agreement is attached to this proxy statement/prospectus as Annex A . Easterly's stockholders are being asked to consider and vote upon a proposal to approve and adopt the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger.

This proxy statement/prospectus and its Annexes contain important information about the proposed Merger and the other matters to be acted upon at the Easterly special meeting. You should read this proxy statement/prospectus and its Annexes carefully and in their entirety.

Q:

What will happen in the Merger?

A:

Pursuant to the Merger, among other things:

•

Merger Sub will merge with and into Easterly, with Easterly surviving the Merger as a wholly owned subsidiary of Sirius Group.

•

Upon the effectiveness of the Merger, all shares of Easterly common stock (other than (i) shares of Easterly common stock with respect to which an Easterly stockholder has validly exercised its redemption rights, and that will be redeemed as provided for by Easterly's charter, (ii) shares of Easterly common stock held by Easterly as treasury stock or owned by Easterly, Sirius Group, Merger Sub, or any wholly owned subsidiary of Easterly or Sirius Group, which will be cancelled for no consideration and (iii) shares of Easterly common stock held by the Sponsor that will be cancelled pursuant to the Sponsor Letter) will be converted into Sirius Group common shares at the Exchange Ratio.

•

Each issued and outstanding public warrant to acquire shares of Easterly common stock will cease to represent a right to acquire shares of Easterly common stock and will be converted into a converted warrant. The number of Sirius Group common shares subject to each converted warrant will be equal to the number of shares of Easterly common stock subject to each Easterly warrant immediately prior to the closing of the Merger multiplied by the Exchange Ratio, and such converted warrant will have an exercise price per Sirius Group common share equal to the exercise price per share of Easterly common stock subject to such Easterly warrant immediately prior to the closing of the Merger divided by the Exchange Ratio.

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Q:

Following the Merger, will Easterly's securities continue to trade on a stock exchange?

A:

No, Easterly's units, common stock and warrants will no longer be listed on the Nasdaq Capital Market. Prior to the closing, Easterly's units, which currently are traded under the symbol "EACQU," will separate into their components of one share of Easterly common stock and one half of a warrant to purchase one share of Easterly common stock, which will be exchanged for Sirius Group common shares and become the converted warrants, respectively.

Q:

Following the Merger, will Sirius Group's securities trade on a stock exchange?

A:

Sirius Group has applied to list the Sirius Group common shares and converted warrants on the Nasdaq Stock Market under the symbols "SG" and "SGW," respectively, effective as of the closing of the Merger. The listing of the Sirius Group common shares on the Nasdaq Stock Market, subject to official notice of issuance, is a condition to the completion of the transactions contemplated by the Merger Agreement. This listing condition may be waived by Sirius Group and Easterly.

Q:

What happens to the capital stock of Easterly in the Merger?

A:

There currently are 19,208,407 shares of Easterly common stock issued and outstanding, consisting of:

•

14,208,407 shares held by public stockholders; and

•

5,000,000 Founder Shares held by the Sponsor and Easterly's original independent directors.

Upon the closing of the Merger, all shares of Easterly common stock (other than (i) shares of Easterly common stock with respect to which an Easterly stockholder has validly exercised its redemption rights, and that will be redeemed as provided for by Easterly's charter, (ii) shares of Easterly common stock held by Easterly as treasury stock or owned by Easterly, Sirius Group or Merger Sub or any wholly owned subsidiary of Easterly or Sirius Group, which will be cancelled for no consideration, and (iii) shares of Easterly common stock held by the Sponsor that will be cancelled pursuant to the Sponsor Letter) will be converted into Sirius Group common shares at the Exchange Ratio.

The Exchange Ratio will be determined prior to the closing of the Merger and will be equal to a fraction determined by dividing (i) the estimated amount of cash per public share of Easterly common stock in the Trust Account immediately prior to the closing of the Merger by (ii) (x) 1.05 multiplied by (y) the Sirius Group September 30 Adjusted DBVPS. The Sirius Group September 30 Adjusted DBVPS is calculated by dividing (i) the book value of Sirius Group determined based on GAAP on a consolidated basis, based on the final, Sirius Group board of directors approved, unaudited GAAP consolidated financial statements of Sirius Group for the nine months ended September 30, 2018, decreased by the $7 million deferred underwriting fee payable by Easterly to Citigroup Global Markets Inc. as underwriter of the IPO, and as adjusted by the GAAP accounting effect of the redemption of the Sirius Group Series A redeemable preference shares by (ii) the sum of (x) the fully diluted number of Sirius Group common shares issued and outstanding as of September 30, 2018 and (y) 593,000 Sirius Group common shares. If an estimate of the Sirius Group September 30 Adjusted DBVPS is used to determine the Exchange Ratio at the closing of the Merger, then the Merger Agreement provides for a post-closing adjustment if such estimate is different than the actual Sirius Group September 30 Adjusted DBVPS as finally determined after the closing of the Merger. Such adjustment will result in either (x) the issuance of new Sirius Group common shares or a payment of cash by Sirius Group to CM Bermuda, if the Exchange Ratio is greater than it would have been using the actual Sirius Group September 30 Adjusted DBVPS or (y) the surrender to Sirius Group of Sirius Group

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common shares owned by CM Bermuda or a payment of cash to Sirius Group from CM Bermuda if the Exchange Ratio is less than it would have been using the actual Sirius Group September 30 Adjusted DBVPS.

Pursuant to the Sponsor Letter, the Sponsor will surrender and Easterly will cancel for no consideration between 3,328,000 and 4,528,000 (or such higher number of shares based on the adjustment described below) shares of Easterly common stock owned by the Sponsor, which amount will be determined at the Effective Time as follows: The base number of 3,928,000 canceled shares will be (i) decreased by 0.50 of a share of Easterly common stock for every $100 that the sum of (x) cash in the Trust Account at the closing of the Merger plus (y) the proceeds of any private placement of Sirius Group common shares (or securities convertible into Sirius Group common shares) in connection with the Merger (the sum of (x) and (y), the " Amount Raised ") is greater than $120 million (provided, that if the Amount Raised is greater than or equal to $150 million, then, solely with respect to any portion of the Amount Raised that is funded from certain designated investors in such private placement, the number of canceled shares will be decreased by 0.25 (in lieu of 0.50) of a share of Easterly common stock for every $100 of the Reduced Rate Amount (as defined below)) or (ii) increased by 0.50 of a share of Easterly common stock for every $100 that the Amount Raised is less than $120 million. Notwithstanding the foregoing, the minimum number of canceled shares will be 3,328,000 and the maximum number of canceled shares will be 4,528,000, except that the Sponsor also agreed to surrender additional shares (which could result in more than 4,528,000 shares surrendered) in certain circumstances if the amount per share equal to (x) 1.05 multiplied by (y) the Sirius Group September 30 Adjusted DBVPS used in the calculation of the Exchange Ratio, as adjusted for the value of the warrants issued in the Sirius Group Private Placement, is less than $17.39. If the proceeds raised from the Sirius Group Private Placement Investors is less than $213 million (other than as a result of an investor failing to fund its obligations in breach of its subscription agreement at a time when Sirius Group is not then in material breach of any of its representations, warranties, covenants or agreements set forth in such subscription agreement at the time of such investor's breach of such subscription agreement), the proceeds of the Sirius Group Private Placement will be deemed to be $213 million for purposes of calculating the Amount Raised. The " Reduced Rate Amount " means the lesser of (a) the Amount Raised minus $150 million and (b) the Amount Raised that is funded from certain designated investors in such private placement.

In addition, there currently are 16,750,000 warrants for Easterly common stock outstanding, consisting of:

•

10,000,000 public warrants; and



•

6,750,000 Private Placement Warrants held by the Sponsor.

Pursuant to the Sponsor Letter, the Sponsor has agreed to cancel the 6,750,000 Private Placement Warrants at the closing of the Merger. Pursuant to the Merger Agreement, each issued and outstanding public warrant stock will cease to represent a right to acquire shares of Easterly common stock and will be converted into a converted warrant. The number of Sirius Group common shares subject to converted warrants will be equal to the number of shares of Easterly common stock subject to each Easterly warrant immediately prior to the closing of the Merger multiplied by the Exchange Ratio, and such converted warrant will have an exercise price per Sirius Group common share equal to the exercise price per share of Easterly common stock subject to such Easterly warrant immediately prior to the closing of the Merger divided by the Exchange Ratio.

The converted warrants become exercisable 30 days after the completion of Merger and expire at 5:00 p.m. New York City time, five years after the completion of the Merger or earlier upon redemption or liquidation. Once the warrants become exercisable, Sirius Group may redeem the

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issued and outstanding warrants in whole and not in part at a price of $0.01 per warrant, if the last sale price of Sirius Group common shares for any 20 trading days within a 30-trading day period equals or exceeds the price determined by dividing $18.00 by the Exchange Ratio. There will be a substantial number of converted warrants to purchase Sirius Group common shares issued and outstanding after the closing of the Merger. To the extent such converted warrants are exercised, additional Sirius Group common will be issued, which will result in dilution to the holders of Sirius Group common shares and increase the number of shares eligible for resale in the public market. Easterly public stockholders will be diluted by these issuances unless they elect to redeem their shares in connection with the Merger. Sales of substantial numbers of such shares in the public market or the fact that such converted warrants may be exercised could adversely impact the market price of Sirius Group common shares and the converted warrants.

Q:

What is the value of the Merger consideration to be received by Easterly stockholders?

A:

Based on a per share value equal to (i) 1.05 multiplied by (ii) the Sirius Group September 30 Adjusted DBVPS, which is estimated as of August 31, 2018 to be $17.77, the aggregate value of the Merger consideration to be received by the Easterly stockholders (including the Sponsor) in respect of their shares of Easterly common stock pursuant to the Merger Agreement is estimated to be $165.2 million. Easterly has not obtained an opinion from an independent financial advisor in connection with the Merger and, consequently, there is no assurance from an independent source that the price Sirius Group is paying for Easterly is fair to Easterly's stockholders from a financial point of view.

Q:

How will the Merger impact the Sirius Group shares issued and outstanding after the Merger?

A:

Based on the number of shares of Easterly common stock and Easterly warrants outstanding on August 31, 2018, Sirius Group expects to issue or reserve for issuance to Easterly public stockholders approximately 8.3 million common shares pursuant to the Merger Agreement (excluding 5.9 million Sirius Group common shares issuable upon exercise of the converted warrants). Sirius Group also expects to issue approximately 1.0 million common shares to the Sponsor, resulting in a total of approximately 9.3 million Sirius Group common shares issued in exchange for outstanding shares of Easterly common stock pursuant to the Merger Agreement. Upon the closing of the Merger, Sirius Group's existing controlling shareholder, CM Bermuda, is expected to own approximately 83.7% of Sirius Group, the Sirius Group Private Placement Investors are expected to own approximately 8.9% of Sirius Group, Easterly's public stockholders (excluding Warrant holders) are expected to own approximately 6.6% of Sirius Group and the Sponsor and Easterly's directors and executive officers are expected to own approximately 0.8% of Sirius Group. The foregoing amounts assume that (i) the Exchange Ratio is equal to 0.586, (ii) no Easterly stockholders exercise their redemption rights in connection with the Merger Proposal, (iii) the Sponsor and Easterly's original independent directors retain 1.0 million shares of Easterly common stock after giving effect to the transactions contemplated by the Sponsor Letter, (iv) Sirius Group issues 11.4 million common shares and Series B preference shares convertible into common shares in connection with the Sirius Group Private Placement, (v) Sirius Group redeems 14.1 million common shares from CM Bermuda for approximately $250 million pursuant to the redemption transaction described herein and (vi) all of the issued and outstanding Sirius Group Series A redeemable preference shares are redeemed for $95 million in cash prior to the closing of the Merger. Further, such percentages do not take into account (x) the issuance of any Sirius Group common shares upon the exercise of the converted warrants that may remain issued and outstanding following the Merger or that are issued pursuant to the Sirius Group Private Placement or (y) the issuance of up to 14.1 million Sirius Group common shares reserved for issuance pursuant to Sirius Group's Long Term Incentive Plan and 2018 Omnibus Incentive Plan. If the facts differ from these assumptions, Easterly's stockholders may experience dilution of their

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ownership interest unless they elect to have their shares of Easterly common stock redeemed in connection with the Merger Proposal. See the section entitled " Proposal No. 1—The Merger Proposal—The Merger Agreement—Merger Consideration" beginning on page 86 and " Security Ownership of Certain Beneficial Owners and Management " beginning on page 341 for further information.

Q:

How has the announcement of the Merger affected the trading price of the Easterly common stock and the public warrants?

A:

On June 22, 2018, the last trading date immediately prior to the announcement of the Merger, the closing trading prices of a share of Easterly common stock and a public warrant on the Nasdaq Capital Market were $10.30 and $0.32, respectively. On [                    ], 2018, the date immediately prior to the date of this proxy statement/prospectus, the closing trading prices of a share of Easterly common stock and a public warrant on the Nasdaq Capital Market were $[            ] and $[            ], respectively.

Q:

What is the nature of Sirius Group's business and operations?

A:

Sirius Group is a Bermuda exempted company whose principal businesses are conducted through its insurance and reinsurance subsidiaries and other affiliates. Sirius Group's subsidiaries, including Sirius Bermuda Insurance Company Ltd. (" Sirius Bermuda "), Sirius International Insurance Corporation (" Sirius International "), Sirius America Insurance Company (" Sirius America ") and Lloyd's Syndicate 1945 (" Syndicate 1945 "), provide insurance, reinsurance and insurance services on a worldwide basis. Sirius Group writes treaty and facultative reinsurance, as well as primary insurance business. The majority of Sirius Group's treaty reinsurance premiums are derived from proportional and excess of loss reinsurance contracts, which in 2017 amounted to 44% and 30%, respectively, of its total net written premiums, while primary business represented 26% of total net written premiums. For more information about Sirius Group, see the sections entitled " Information About Sirius Group ," " Management's Discussion and Analysis of Financial Condition and Results of Operations of Sirius Group " and " Management of Sirius Group " beginning on pages 152, 196 and 274, respectively.

Q:

What revenue and net income has Sirius Group generated in 2017, 2016 and 2015?

A:

For the years ended December 31, 2017, 2016 and 2015, Sirius Group had total revenues approximately $1,134 million, $995 million and $1,107 million, respectively, with net (loss) income of $(156) million, $33 million and $291 million, respectively. Basic (loss) earnings per share for the years ended December 31, 2017, 2016 and 2015 was $(1.30), $0.27 and $2.43, respectively. See " Selected Consolidated Historical Financial Data of Sirius Group " beginning on page 124 and " Management's Discussion and Analysis of Financial Condition and Results of Operations of Sirius Group " beginning on page 196 for additional information.

Q:

Who will manage the combined company following the Merger?

A:

It is anticipated that the current executive officers of Sirius Group will manage the combined company upon the completion of the Merger. Additionally, it is anticipated that the board of directors of the combined company will be comprised of the current members of the board of directors of Sirius Group, and additional independent directors to be identified by Sirius Group. See the section entitled " Management of Sirius Group " beginning on page 274 for further information.

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Q:

Is the Merger the first step in a "going-private" transaction?

A:

Easterly does not intend for the Merger to be the first step in a "going-private" transaction. One of the primary purposes of the Merger is to provide a platform for Sirius Group to access the U.S. public markets.

Q:

What conditions must be satisfied to complete the Merger?

A:

There are a number of closing conditions in the Merger Agreement, including, but not limited to, the following:

•

holders of at least a majority of the outstanding shares of Easterly common stock must approve and adopt the Merger Agreement;

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the Sirius Group common shares issuable pursuant to the Merger Agreement and upon exercise of the converted warrants must be approved for listing on the Nasdaq Stock Market, subject to official notice of issuance;

•

there must not be in effect any order by a governmental entity of competent jurisdiction which prohibits, restrains or makes illegal the consummation of the transactions contemplated by the Merger Agreement;

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Sirius Group's Registration Statement on Form S-4, of which this proxy statement/prospectus forms a part, must have become effective under the Securities Act and not be the subject of any stop order, and no proceedings for that purpose shall have been initiated or threatened by the SEC and not withdrawn; and

•

there must not have been any event or circumstance which resulted or that would reasonably be expected to result in a material adverse effect of Sirius Group or Easterly that is continuing.

In addition, under Easterly's charter, Easterly may not redeem or repurchase Easterly common stock to the extent that such redemption would result in Easterly's failure to have net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) in excess of approximately $5 million.

For a summary of all of the conditions that must be satisfied or waived prior to completion of the Merger, see the section entitled " Proposal No. 1—The Merger Proposal—The Merger Agreement " beginning on page 86.

Q:

What interests do Easterly's directors and executive officers have in the Merger that could conflict with a public stockholder?

A:

Easterly's directors and executive officers may have interests in the Merger that are different from, in addition to or in conflict with, yours. These interests include:

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the 400,000 to 1.6 million total Founder Shares that the Sponsor (or its members) will hold immediately prior to the Merger, which will be exchanged for Sirius Group common shares at the Exchange Ratio in connection with the Merger;

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the 24,000 Founder Shares that one of Easterly's independent directors holds as of August 31, 2018, which will be exchanged for Sirius Group common shares at the Exchange Ratio in connection with the Merger;

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if Easterly is unable to complete a business combination within the required time period, the Convertible Promissory Note issued to the Sponsor, in the amount of $895,000 at August 31, 2018 plus accrued interest, will not be repaid and all amounts owed thereunder will be forgiven

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except to the extent that Easterly has funds available to it outside of the Trust Account to repay such amounts;

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if Easterly is unable to complete a business combination within the required time period, Easterly's Chairman, its Chief Executive Officer and David Cody will be personally liable to ensure that the proceeds in the Trust Account are not reduced by the claims of target businesses or claims of vendors or other entities that are owed money by Easterly for services rendered or contracted for or products sold to Easterly, but only if such a vendor or target business has not executed a waiver of claims against the Trust Account and except as to any claims under Easterly's indemnity of the underwriters; and



•

the continued indemnification of current directors and officers of Easterly and the continuation of directors' and officers' liability insurance after the Merger.

Further, each of Easterly's directors, directly or indirectly, holds Founder Shares that are not subject to redemption and certain of Easterly's directors indirectly hold Private Placement Warrants that would retire worthless if a business combination is not consummated. As a result, Easterly's directors have a financial incentive to see a business combination consummated rather than lose whatever value is attributable to the Founder Shares and Private Placement Warrants. These interests may influence Easterly's directors in making their recommendation that you vote in favor of the Merger Proposal, and the transactions contemplated thereby.

Q:

What interests do Sirius Group's directors and executive officers have in the Merger?

A:

Sirius Group's directors and executive officers may have interests in the Merger that are different from, in addition to or in conflict with, yours. These interests include:

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the directors and executive officers of Sirius Group will continue to be the directors and executive officers of the combined company;

•

in connection with the Merger, each executive officer of Sirius Group will receive a performance share unit award granted under the 2018 Omnibus Incentive Plan, with the target number of performance share units equal to a specified dollar value divided by the per share value of Sirius Group common shares at the closing of the Merger. The performance share unit awards have been allocated to the executive officers as follows, based on the grant date value of the award at target levels of performance: Mr. Waters—$2,600,000; each of Mr. Boxer, Ms. Cramér Manhem and Mr. Oberting—$1,800,000; and Mr. Davis—$700,000. The performance share unit awards will be subject to vesting conditions and a commitment by the executive officer to purchase Sirius Group common shares having a value equal to the target award granted to the executive officer;

•

in connection with the Merger, Sirius Group has implemented an Employee Share Purchase Program, which provides all employees of Sirius Group with a one-time opportunity to purchase between 100 and 1,000 Sirius Group common shares at a price equal to 85% of market value for the first 100 shares and 100% of market value for the next 900 shares. For this purpose, the market value of the Sirius Group common shares will be equal to 1.05 times the Sirius Group September 30 Adjusted DBVPS. Employees have the option of paying for the shares upfront or, in the case of employees who are not executive officers, through a loan that is repaid over a two-year period through payroll deductions;

•

in connection with the Merger, the Compensation Committee amended the Sirius Group 2016 Long Term Incentive Plan (the " 2016 LTIP ") to provide for continued vesting of outstanding awards in the event of a termination of employment by Sirius Group without cause or by the executive officer due to good reason outside of the 24-month change in control period already provided for under the 2016 LTIP. In these qualifying terminations of employment events, each

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of our other named executive officers will continue to vest in outstanding awards for 12 months following a termination of employment. The ability to receive payments during these vesting continuation periods will be subject to actual performance; and

•

in connection with the Merger, Sirius Group adopted the Sirius Group Severance and Change in Control Plan (the " Executive Severance Plan "), which provides executive officers with severance and post-employment benefits in the event of (i) an involuntary termination without cause or (ii) a resignation by the executive officer for good reason. For these qualifying terminations of employment prior to a change in control, our named executive officers will receive severance benefits equal to one times base salary, any earned but unpaid bonus for the year prior to termination, a pro-rata bonus for the year of termination, based on actual performance, and medical continuation benefits for 12 months. In the event of a qualifying termination of employment following a change in control, the severance benefits are the same, except the severance pay is increased to two times base salary for the named executive officers, the medical continuation period is increased to two years for the named executive officers, and the prorated bonus for the year of the termination will be paid at the target level of performance. Additionally, the Executive Severance Plan provides that in the event of a qualifying termination within 24 months following a change in control, all outstanding equity compensation awards will become fully vested, with the attainment or deemed attainment of any applicable performance conditions determined under the terms of the applicable equity compensation plan or award agreements. In order to be eligible to receive severance payments, pursuant to the Executive Severance Plan, the executive officer must execute a release in Sirius Group's favor. The Executive Severance Plan provides that, to the extent that Mr. Waters' or Ms. Cramér Manhem's employment agreements provide additional severance protections, they will continue to receive the employment agreement severance protections, to the extent they do not result in duplicative benefits under the Executive Severance Plan.

Q:

What happens to Easterly if the Merger is not consummated?

A:

There are certain circumstances under which the Merger Agreement may be terminated. See the section entitled " Proposal No. 1—The Merger Proposal—The Merger Agreement " beginning on page 86 for information regarding the parties' specific termination rights.

If, as a result of the termination of the Merger Agreement or otherwise, Easterly is unable to complete the Merger or another business combination transaction by November 30, 2018, Easterly's charter provides that Easterly will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem 100% of the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest earned on the funds held in the Trust Account and not previously released to Easterly to pay its franchise and income taxes (which interest will be net of taxes payable and reduced by up to $100,000 to pay dissolution expenses), divided by the number of then outstanding public shares, which redemption will completely extinguish public stockholders' rights as stockholders (including the right to receive further liquidation distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of Easterly's remaining stockholders and Easterly's board of directors, dissolve and liquidate, subject in each case to its obligations under Delaware law to provide for claims of creditors and the requirements of other applicable law. See the section entitled " Risk Factors—If Easterly is unable to effect a business combination by November 30, 2018, Easterly will be forced to liquidate and the public warrants will expire worthless " on page 71 and "—If Easterly is forced to liquidate, its stockholders may be held liable for claims by third parties against Easterly to the extent of distributions received by them " beginning on page 72.

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Holders of the Founder Shares have waived any right to any liquidation distribution with respect to those shares.

In the event of liquidation, there will be no distribution with respect to Easterly's outstanding pubic warrants. Accordingly, the public warrants will expire worthless.

Q:

What happens to the funds held in the Trust Account upon consummation of the Merger?

A:

If the Merger is consummated, the funds held in the Trust Account will be released to (i) the surviving company for general corporate purposes, including making loans or contributing cash to other affiliates for working capital, organic growth and future potential acquisitions, (ii) pay unpaid franchise and income taxes of Easterly, (iii) Easterly stockholders who properly exercise their redemption rights, and (iv) pay up to $2 million of Easterly's liabilities, fees, costs and expenses and the $7 million deferred underwriting fee. The deferred underwriting fee will not change as a result of the amount of redemptions of Easterly common stock, and will not reduce the per-share amount that Easterly will distribute to stockholders who properly redeem their shares. The deferred underwriting fee will not be paid in the event that the Merger is not completed. See the section entitled " Use of Proceeds " on page 123.

Following the consummation of the Merger, the combined company will be entitled to use the funds in the Trust Account. Other than the foregoing uses, the combined company does not have specific plans for any funds remaining from the Trust Account and will have broad discretion regarding how to use the funds that remain. These funds could be used in a manner with which you may not agree or applied in ways that do not improve the combined company's results of operations or increase the value of your investment.

Q:

When is the Merger expected to be completed?

A:

It is currently anticipated that the Merger will be consummated promptly following the Easterly special meeting of stockholders, provided that all other conditions to the consummation of the Merger have been satisfied or waived. For a description of the conditions to the completion of the Merger, see the section entitled " The Merger Agreement—Conditions to Closing of the Merger " beginning on page 90.

Q:

Do Easterly stockholders have appraisal rights if they object to the proposed Merger?

A:

No. There are no appraisal rights available to holders of Easterly common stock in connection with the Merger.

About the Redemption Rights of Easterly Public Stockholders

Q:

Do I have redemption rights?

A:

If you are a holder of Easterly public shares, you may have your public shares redeemed for cash equal to your pro rata share of the aggregate amount on deposit in the Trust Account, which holds the proceeds of the IPO, as of two business days prior to the consummation of the Merger, including interest earned on the funds held in the Trust Account and not previously released to Easterly to pay its franchise and income taxes, upon the consummation of the Merger. For illustrative purposes, based on funds in the Trust Account of approximately $148.0 million on August 31, 2018, the estimated per share redemption price would have been approximately $10.41. This is slightly more than the $10.00 initial public offering price of Easterly's units. Additionally, shares properly tendered for redemption will only be redeemed if the Merger is consummated; otherwise, holders of such shares will only be entitled to a pro rata portion of the Trust Account including interest earned on the funds held in the Trust Account and not previously released to

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Easterly to pay franchise and income taxes (which interest will be net of taxes payable and reduced by up to $100,000 to pay dissolution expenses) in connection with the liquidation of the Trust Account.

Q:

Can the Sponsor or the Easterly independent directors redeem their Easterly common stock?

A:

All of the holders of Founder Shares, which includes the Sponsor and Easterly's original independent directors, have agreed to waive their redemption rights with respect to their Founder Shares and have agreed to waive their redemption rights with respect to any public shares that they may have acquired during or after the IPO in connection with the completion of the Merger. The Founder Shares will be excluded from the pro rata calculation used to determine the per-share redemption price.

Q:

Is there a limit on the number of shares I may redeem?

A:

A public stockholder, together with any of his, her or its affiliates or any other person with whom he, she or it is acting in concert or as a "group" (as defined in Section 13(d)(3) of the Exchange Act) will be restricted from seeking redemption rights with respect to 15% or more of the public shares of Easterly common stock. Accordingly, all shares in excess of 15% owned by a holder will not be redeemed for cash. On the other hand, a public stockholder who holds less than 15% of the public shares of common stock may redeem all of the public shares held by him, her or it for cash.

Q:

How will the level of redemptions affect the Merger?

A:

The fraction of a Sirius Group common share issuable for each share of Easterly common stock will not be impacted by the level of redemptions.

Q:

How will the level of redemptions affect the combined company?

A:

The number of redemptions requested by Easterly stockholders would affect the amount of cash from the Trust Account available for general corporate purposes following the Merger. Each redemption of public shares by Easterly's public stockholders will decrease the amount in the Trust Account, which was approximately $148.0 million as of August 31, 2018. There is no specified maximum redemption threshold under Easterly's charter. In no event, however, will Easterly redeem public shares in an amount that would cause its net tangible assets to be less than $5,000,001. In addition, the number of redemptions requested by Easterly stockholders may result in a less liquid trading market for the combined company's common shares, fewer shareholders and the potential inability to meet Nasdaq's listing standards.

Q:

Will how I vote affect my ability to exercise redemption rights?

A:

No. You may exercise your redemption rights whether you vote your shares of Easterly common stock for or against the Merger Proposal. As a result, the Merger Proposal can be approved by stockholders who will redeem their shares and no longer remain stockholders.

Q:

How do I exercise my redemption rights?

A:

In order to exercise your redemption rights, you must, prior to 5:00 p.m. Eastern time on [                    ], 2018 (two business days before the Easterly special meeting), (i) if you hold Easterly units, elect to separate your Easterly units into the underlying public shares and public warrants prior to exercising your redemption rights with respect to your public shares, (ii) submit a written request to Easterly's transfer agent that it redeem your public shares for cash, and (iii) deliver your stock to Easterly's transfer agent physically or electronically through The Depository Trust Company (" DTC "), in each case in accordance with the procedures described in this proxy

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statement/prospectus. The address of Continental Stock Transfer & Trust Company, Easterly's transfer agent, is listed under the question " Who can help answer my questions? " below. Any demand for redemption, once made, may be withdrawn at any time until the deadline for exercising redemption requests and thereafter, with Easterly's consent, until the vote is taken with respect to the Merger. If you delivered your shares for redemption to Easterly's transfer agent and decide within the required timeframe not to exercise your redemption rights, you may request that Easterly's transfer agent return the shares (physically or electronically). You may make such request by contacting Easterly's transfer agent at the phone number or address listed under " Who can help answer my questions? " below.

Q:

What are the U.S. federal income tax consequences as a result of the Merger?

A:

Easterly and Sirius Group intend to report the Merger as a tax-deferred transaction for United States federal income tax purposes pursuant to Section 368 of the Code. Assuming such treatment is respected, holders of Easterly common stock generally will not recognize gain or loss for U.S. federal income tax purposes as a result of the exchange of their Easterly common stock for Sirius Group common shares (except with respect to cash received in lieu of fractional shares). Neither Easterly nor Sirius Group intends to request any ruling or other guidance from the IRS on the United States federal income tax treatment of the Merger, neither is receiving an opinion of counsel regarding such treatment, and no assurance can be given that the IRS would not challenge such treatment in light of the specific terms of the Merger, the post-closing adjustments with Sirius Group common shares to reflect the exchange ratio and related transactions. You are strongly urged to consult with your own tax advisor to determine the particular U.S. federal, state or local or foreign income or other tax consequences of the Merger to you. See the section entitled " Material Tax Consequences—Material U.S. Tax Consequences " beginning on page 139.

Q:

What are the U.S. federal income tax considerations of exercising my redemption rights?

A:

Easterly stockholders who exercise their redemption rights to receive cash from the Trust Account in exchange for their shares of Easterly common stock generally will be required to treat the transaction as either a sale of such shares or a distribution with respect to such holder's shares of Easterly common stock. See the section entitled " Proposal No. 1—The Merger Proposal—U.S. Federal Income Tax Considerations of Redeeming Easterly Common Stock " beginning on page 117.

Q:

If I am an Easterly warrant holder, can I exercise redemption rights with respect to my warrants?

A:

No. There are no redemption rights with respect to Easterly's warrants.

About the Easterly Special Meeting

Q:

What is being voted on at the Easterly special meeting?

A:

Below are the proposals on which Easterly's stockholders are being asked to consider and vote upon at the Easterly special meeting.

1.

Proposal No. 1—The Merger Proposal —To approve and adopt the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger; and

2.

Proposal No. 2—The Adjournment Proposal— To approve the adjournment of the Easterly special meeting to a later date or dates, if necessary, to permit further solicitation of proxies in the event that, based upon the tabulated vote at the time of the Easterly special meeting, there are not sufficient votes to approve one or more proposals presented to Easterly's stockholders for vote at such special meeting. This proposal will only be presented at the

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Easterly special meeting if there are not sufficient votes to approve the one or more proposals presented to Easterly's stockholders for vote at such special meeting.

Your vote is important. You are encouraged to submit your proxy as soon as possible after carefully reviewing this proxy statement/prospectus and its Annexes.

Q:

Are the Merger Proposal and the Adjournment Proposal conditioned on each other?

A:

No. The Merger Proposal is not conditioned on the approval of the Adjournment Proposal and the Adjournment Proposal is not conditioned on the approval of the Merger Proposal.

Q:

What happens to Easterly if Easterly stockholders do not approve the Merger Proposal?

A:

If Easterly stockholders do not approve the Merger Proposal, then Easterly cannot consummate the Merger. If Easterly does not consummate the Merger and fails to complete an initial Merger by November 30, 2018, Easterly will be required to dissolve and liquidate the Trust Account.

Q:

Why is Easterly providing its stockholders with the opportunity to vote on the Merger Proposal?

A:

The Merger Proposal provides for the approval and adoption by Easterly stockholders of the Merger Agreement and the Merger. Easterly's charter requires that it provide all holders of its public shares with the opportunity to have their public shares redeemed upon the consummation of its initial business combination in conjunction with either a tender offer or a stockholder vote. For business and other reasons, Easterly has elected to provide Easterly stockholders with the opportunity to have their public shares redeemed in connection with a stockholder vote rather than pursuant to a tender offer. As a result, Easterly public stockholders will have the opportunity to redeem their public shares in connection with the closing of the Merger.

Q:

What happens if I sell my shares of Easterly common stock before the Easterly special meeting of stockholders?

A:

The record date for the Easterly special meeting of stockholders will be earlier than the date of the special meeting. If you transfer your shares of Easterly common stock after the record date, but before the Easterly special meeting of stockholders, unless the transferee obtains from you a proxy to vote those shares, you will retain your right to vote at the Easterly special meeting of stockholders.

Q:

What vote is required to approve the proposals presented at the Easterly special meeting of stockholders?

A:

The approval of the Merger Proposal requires the affirmative vote of the holders of a majority of the outstanding shares of Easterly common stock. Accordingly, an Easterly stockholder's failure to vote by proxy or to vote in person at the Easterly special meeting of stockholders, an abstention from voting or a broker non-vote will have the same effect as a vote "AGAINST" the Merger Proposal. The approval of the Adjournment Proposal requires the affirmative vote of holders of a majority of the shares of Easterly common stock that are voted on such proposal at the Easterly special meeting of stockholders. Accordingly, an Easterly stockholder's failure to vote by proxy or to vote in person at the Easterly special meeting of stockholders or an abstention from voting will have no effect on the outcome of any vote on the Adjournment Proposals. A broker non-vote will have no effect on the Adjournment Proposal.

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Q:

How many votes do I have at the Easterly special meeting of stockholders?

A:

For each proposal, Easterly's stockholders are entitled to one vote at the Easterly special meeting for each share of Easterly common stock held of record as of the record date. As of the close of business on the record date, there were 19,208,407 outstanding shares of Easterly common stock.

Q:

What constitutes a quorum at the Easterly special meeting of stockholders?

A:

Holders of a majority in voting power of Easterly's common stock issued and outstanding and entitled to vote at the Easterly special meeting, present in person or represented by proxy, constitute a quorum. In the absence of a quorum, a majority of Easterly stockholders, present in person or represented by proxy, will have power to adjourn the Easterly special meeting. As of the record date for the Easterly special meeting, the presence in person or by proxy of holders of at least 9,604,204 shares of Easterly common stock would be required to achieve a quorum.

Q:

How will the Sponsor and Easterly's directors and officers vote?

A:

In connection with the IPO, Easterly entered into agreements with the Sponsor and with Easterly's original independent directors, pursuant to which each agreed to vote their Founder Shares and any other shares acquired during and after the IPO in favor of the Merger Proposal. Additionally, the Sponsor Letter requires that Sponsor vote its shares of Easterly common stock in favor of the Merger. Neither the Sponsor nor Easterly's directors or officers have purchased any shares during or after the IPO and neither Easterly nor the Sponsor, its directors or its officers have entered into agreements, and are not currently in negotiations, to purchase shares. Currently, the Sponsor, Easterly's original independent directors and their permitted transferees own 25.8% of the issued and outstanding shares of Easterly common stock, consisting of 100% of the Founder Shares.

Q:

How do I vote?

A:

If you were a holder of record of Easterly common stock on [                    ], 2018, the record date for the Easterly special meeting, you may vote or have your shares voted with respect to the applicable proposals:

•

in person at the Easterly special meeting of stockholders; or

•

by submitting a proxy to vote by completing, signing, dating and returning the enclosed proxy card in the postage-paid envelope provided.

If you hold your shares in "street name," which means your shares are held of record by a broker, bank or other nominee, you should contact your broker, bank or nominee to ensure that votes related to the shares you beneficially own are properly counted. In this regard, you must provide the record holder of your shares with instructions on how to vote your shares or, if you wish to attend the Easterly special meeting of stockholders and vote in person, obtain a proxy from your broker, bank or nominee.

Q:

What will happen if I sign and return my proxy card without indicating how I wish to vote?

A:

If you are a record holder, then signed and dated proxies received by Easterly without an indication of how the stockholder of record intends to vote on a proposal will be voted in favor of each proposal presented to the stockholders.

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Q:

If my shares are held in "street name," will my broker, bank or nominee automatically vote my shares for me?

A:

No, except with respect to the Adjournment Proposal. Under the rules of various national and regional securities exchanges, your broker, bank or nominee cannot vote your shares with respect to non-discretionary matters unless you provide instructions on how to vote in accordance with the information and procedures provided to you by your broker, bank or nominee. Except for the Adjournment Proposal, we believe the proposals presented to the stockholders will be considered non-discretionary and therefore your broker, bank or nominee cannot vote your shares without your instruction. If you do not provide instructions with your proxy, your broker, bank or nominee may deliver a proxy card expressly indicating that it is NOT voting your shares; this indication that a broker, bank or nominee is not voting your shares is referred to as a "broker non-vote." Broker non-votes will not be counted for the purpose of determining the existence of a quorum or for purposes of determining the number of votes cast at the Easterly special meeting. Except with respect to the Adjournment Proposal, your broker, bank or nominee can vote your shares only if you provide instructions on how to vote. You should instruct your broker to vote your shares in accordance with directions you provide.

Q:

If I am not going to attend the Easterly special meeting of stockholders in person, should I return my proxy card instead?

A:

Yes. Whether you plan to attend the Easterly special meeting or not, please read this proxy statement/prospectus carefully, and submit your proxy to vote by completing, signing, dating and returning the enclosed proxy card in the postage-paid envelope provided.

Q:

May I change my vote after I have submitted my signed proxy card?

A:

Yes. You may change your vote by sending a later-dated, signed proxy card to Easterly's secretary at the address listed below so that it is received by its secretary prior to the Easterly special meeting of stockholders, or attending the Easterly special meeting in person and vote. You also may revoke your proxy by sending a notice of revocation to Easterly's secretary, which must be received by Easterly's secretary prior to the Easterly special meeting.

Q:

What should I do if I receive more than one set of voting materials?

A:

You may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold your shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold shares. If you are a holder of record and your shares are registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive in order to cast your vote with respect to all of your shares.

Q:

Who will solicit and pay the cost of soliciting proxies?

A:

Easterly will pay the cost of soliciting proxies for the Easterly special meeting. Easterly has engaged Morrow Sodali LLC (" Morrow Sodali ") to assist in the solicitation of proxies for the Easterly special meeting. Easterly has agreed to pay Morrow Sodali a fee of $[            ], plus disbursements. Easterly will reimburse Morrow Sodali for reasonable out-of-pocket expenses and will indemnify Morrow Sodali and its affiliates against certain claims, liabilities, losses, damages and expenses. Easterly also will reimburse banks, brokers and other custodians, nominees and fiduciaries representing beneficial owners of shares of Easterly's common stock for their expenses in forwarding soliciting materials to beneficial owners of Easterly's common stock and in obtaining

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voting instructions from those owners. Easterly's directors, officers and employees, including David Cody, Darrell W. Crate, Avshalom Kalichstein, David W. Knowlton, Neil Medugno, Justin Tuck and Jurgen Lika, may also solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies.

Q:

What do I need to do now if I am an Easterly stockholder?

A:

You are urged to carefully read and consider the information contained in this proxy statement/prospectus, including the Annexes, and to consider how the Merger will affect you as an Easterly stockholder. You should then submit your proxy as soon as possible in accordance with the instructions provided in this proxy statement/prospectus and on the enclosed proxy card or, if you hold your shares through a brokerage firm, bank or other nominee, on the voting instruction form provided by the broker, bank or nominee.

Q:

Who can help answer my questions?

A:

If you have questions about the proposals or if you need additional copies of the proxy statement/prospectus or the enclosed proxy card, you should contact:

Easterly Acquisition Corp.
205 Hudson Street, 7 ^th  Floor
New York, NY 10013
Telephone: (646) 712-8300
Email: info@easterlyacquisition.com

        You may also contact Easterly's proxy solicitor at:

Morrow Sodali LLC
470 West Avenue, 3 ^rd  Floor
Stamford, CT 06902
Stockholders, please call toll free: (800) 662-5200
Banks and Brokerage Firms, please call collect: (203) 658-9400
Email: Easterly.info@morrowsodali.com

        To obtain timely delivery, Easterly's stockholders must request the materials no later than five business days prior to the Easterly special meeting.

        You may also obtain additional information about Easterly from documents filed with the SEC by following the instructions in the section entitled " Where You Can Find More Information " on page 350.

        If you intend to seek redemption of your public shares, you will need to send a letter demanding redemption and deliver your stock (either physically or electronically) to Easterly's transfer agent prior to 5:00 p.m. Eastern time on [                    ], 2018 (two business days before the Easterly special meeting). If you have questions regarding the certification of your position or delivery of your stock, please contact:

Continental Stock Transfer & Trust Company
1 State Street Plaza, 30 ^th  Floor
New York, NY 10004
Attn: Mark Zimkind
Email: mzimkind@continentalstock.com

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