Suggested in comments but I don't know if this is allowed. In any case: I've used an OCR program to copy the contents of the 2.5 pages below. I've used some minimal editing to keep the format vaguely similar, but as this was computerised there may be some errors, so this is community wiki; please fix them as you find them.
June 22, 2013
This letter is to confirm that, per our communications, that MathOverflow ("MathOverflow") agrees that the website, MathOverflow (located at www.mathoverflow.net, www.mathoverflow.com and www.mathoverflow. org (the "MathOverflow Domains"), the assets of which are owned and controlled by MathOverflow, will be upgraded to Stack Exchange, Inc.'s ("Stack Exchange") version 2.0 software model and, in conjunction with this upgrade, MathOverflow accepts Stack Exchange 2.0's Terms of Service (http://stackexchange.com/legal/tems-of-service, the "Terms"), Which shall be incorporated by reference into this letter agreement. In consideration for the foregoing, the parties agree as follows:
StackExchange will upgrade MathOverflow to the Stack Exchange's latest software model, and will incorporate MathOverflow into the Stack Exchange network of websites ("MathOverflow 2.0").
Current MathOverflow moderators will serve as the initial MathOverflow 2.0 moderators ("Moderators"). From time to time, and after consultation with existing Moderators, StackExchange will hold elections for additional Moderators as the need arises.
Before finalization of the MathOverflow 2.0 migration, StackExchange shall create a test version of the website so MathOverflow may test the migration (“Test Site”). The Test Site shall be a fully-functioning, fully operational version of MathOverflow running under the latest Stack Exchange software, which MathOverflow may test "and otherwise use before the migration is complete. MathOverflow and you acknowledge and agree that any changes made by you or MathOverflow in the Test Site will be lost following the final migration to MathOverflow 2.0. The migration will be performed by StackExchange only after receiving written approval from MathOverflow, which approval may be communicated via email. After migration, MathOverflow will remain exclusively located at the MathOverflow Domains.
It is understood that MathOverflow shall consider in the future the placement of certain announcement services like job listings in the future. Stack Exchange shall not run advertisements, including internal advertisements, on MathOverflow 2.0 (or any subsequent version thereof), without specific and advance written consent of the MathOverflow.
The DNS operation of the MathOverflow Domains will be delegated to Stack Exchange but the MathOverflow Domains and their registrations, as well as the trademarks and associated goodwill in "MathOverflow" shall be owned by and remain an asset exclusively of MathOverflow. MathOverflow hereby grants to StackExchange a license to use the trademark "MathOverflow" for the purposes of operating and promoting the MathOverflow forum as contemplated in this letter agreement. StackExchange will not use or register any trademark that is confusingly similar to "MathOverflow."
Subject to Section 8, should MathOverflow wish to migrate its data outside of the Stack Exchange network, Stack Exchange shall, within thirty (30) days of receipt of a written request from MathOverflow, provide MathOverflow with a complete and current database that contains all the data necessary to recreate MathOverflow on MathOverflow's own servers and software. Following such transfer, StackExchange will cease all use of the MathOverflow database.
Each party hereto represents and warrants that: (i) it has sufficient rights to perform its duties and obligations under this letter agreement; and (ii) each party's duties and obligations hereunder shall not violate any agreement, arrangement, commitment or legal restriction to which either party may be bound. MathOverflow further represents and warrants that it owns the MathOverflow forum assets and has sufficient rights to enter into this agreement and to carry out or oversee the fulfillment of its duties and obligations hereunder.
Each party to this letter agreement shall be responsible to perform its obligations at its sole expense, and without charge to or right of reimbursement from the other party. This letter agreement supersedes all proposals, oral or written, all negotiations, conversations, or discussions between or among parties relating to the subject matter of this letter agreement and all past dealing or industry custom. This letter agreement shall be integrated in and form part of the Terms upon execution. All terms and conditions of the Terms shall remain unchanged except as modified in this letter agreement; and the terms of the Terms, as modified by this letter agreement, are hereby ratified and confirmed. Where the terms of the Terms conflict with those of this letter agreement, however, the terms of this letter agreement shall control. This letter agreement may be executed in one or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same agreement. The parties hereto acknowledge that the foregoing services are provided free of charge by Stack Exchange and are provided "AS IS." Additionally, MathOverflow makes no warranties or representations regarding the content of the MathOverflow forum, and all such content is provided to StackExchange "AS IS." Any provisions of this letter agreement that, in order to fulfill the purposes of such provisions, need to survive the termination or expiration of this Agreement, shall be deemed to survive for as long as necessary to fulfill such purposes. StackExchange agrees to ensure that any successor in interest to StackExchange will be bound to the terms of this letter agreement.
CEO and Cofounder
Stack Exchange, Inc.
MathOverflow, through its owner and proprietor Anton Geraschenko, hereby confirms its agreement to the terms set forth above:
Name: Anton Geraschenko
The last page is an "Audit trail" that looks pointless to copy here.