Home/Filings/4/0001104659-26-001374
4//SEC Filing

Protopapas Anna 4

Accession 0001104659-26-001374

CIK 0001442836other

Filed

Jan 5, 7:00 PM ET

Accepted

Jan 6, 4:42 PM ET

Size

48.0 KB

Accession

0001104659-26-001374

Insider Transaction Report

Form 4
Period: 2026-01-06
Transactions
  • Disposition from Tender

    Common Stock

    2026-01-066,7210 total
  • Disposition from Tender

    Common Stock

    2026-01-062,8900 total(indirect: See footnote)
  • Disposition from Tender

    Common Stock

    2026-01-069,6090 total(indirect: See footnote)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-062,4600 total
    Exercise: $9.08Common Stock (2,460 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-062,5000 total
    Exercise: $174.50Common Stock (2,500 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-064800 total
    Exercise: $355.75Common Stock (480 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-067,5190 total
    Exercise: $355.75Common Stock (7,519 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-065420 total
    Exercise: $87.75Common Stock (542 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-068,1370 total
    Exercise: $87.75Common Stock (8,137 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-0610 total
    Exercise: $87.75Common Stock (1 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-06180 total
    Exercise: $87.75Common Stock (18 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-069880 total
    Exercise: $154.00Common Stock (988 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-0611,7610 total
    Exercise: $154.00Common Stock (11,761 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-066650 total
    Exercise: $33.00Common Stock (665 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-069,0430 total
    Exercise: $157.00Common Stock (9,043 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-0611,2500 total
    Exercise: $151.50Common Stock (11,250 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-062,2000 total
    Exercise: $56.50Common Stock (2,200 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-061,1310 total
    Exercise: $102.50Common Stock (1,131 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-065,2270 total
    Exercise: $102.50Common Stock (5,227 underlying)
  • Disposition to Issuer

    Stock Option (right to buy)

    2026-01-061660 total
    Exercise: $174.50Common Stock (166 underlying)
Footnotes (6)
  • [F1]Pursuant to the terms of that certain Agreement and Plan of Merger (the "Merger Agreement"), by and among the Issuer, Day One Biopharmaceuticals, Inc. ("Parent") and Parent's direct wholly-owned subsidiary, Emerald Merger Sub, Inc. ("Purchaser"), dated as of November 12, 2025, the shares (the "Shares") of common stock, par value $0.0001 per share, of the Issuer (the "Common Stock") that were tendered to Purchaser prior to the expiration time of the Offer were exchanged for: (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding (the "Upfront Cash Consideration"), plus (ii) one non-tradeable contingent value right per Share (each, a "CVR"),
  • [F2](continued from footnote 1) which represents the right to receive certain contingent milestone payments of up to an aggregate of $30.25 per CVR in cash, without interest and less any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent (the Upfront Cash Consideration plus one CVR, collectively, the "Offer Price"). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Issuer, effective as of January 6, 2026 (the "Effective Time"), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent.
  • [F3]Pursuant to the terms of the Merger Agreement, effective as of immediately prior to the Effective Time, each option to purchase shares of Common Stock ("Issuer Option") that was outstanding and unexercised as of immediately prior to the Effective Time and had an exercise price per Share that was less than the Upfront Cash Consideration (each, a "Cash-Out Option"), became fully vested and was automatically cancelled and converted into the right to receive, without interest and subject to deduction for any required tax withholding, (i) the Offer Price minus (ii) the exercise price payable per share of Common Stock underlying such Cash-Out Option.
  • [F4]Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the "Acceleration Date"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an "OTM Option"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the "Last Exercise Date"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option.
  • [F5]These Shares were held by the Kinney/Protopapas Family Irrevocable Trust (the "Kinney/Protopapas Trust") for the benefit of the Reporting Person's children. The Reporting Person's spouse is a co-trustee of the Kinney/Protopapas Trust.
  • [F6]These Shares were held by the Anna Protopapas Irrevocable Trust (the "Protopapas Trust") for the benefit of the Reporting Person's spouse and children. The Reporting Person's spouse is the trustee of the Protopapas Trust.

Issuer

Mersana Therapeutics, Inc.

CIK 0001442836

Entity typeother

Related Parties

1
  • filerCIK 0001347582

Filing Metadata

Form type
4
Filed
Jan 5, 7:00 PM ET
Accepted
Jan 6, 4:42 PM ET
Size
48.0 KB