Panacea Innovation Ltd - 28 Nov 2025 Form 4 Insider Report for Atara Biotherapeutics, Inc. (ATRA)

Role
10%+ Owner
Signature
Panacea Innovation Limited By: /s/ James Huang, Founding Managing Partner
Issuer symbol
ATRA
Transactions as of
28 Nov 2025
Transactions value $
-$322,156
Form type
4
Filing time
01 Dec 2025, 17:00:04 UTC
Previous filing
19 Aug 2025
SEC
View on sec.gov

Reporting Owners (2)

Name Relationship Address Signature Signature date CIK
Panacea Innovation Ltd 10%+ Owner C/O MAPLES CORPORATE SERVICES LIMITED,, UGLAND HOUSE, GRAND CAYMAN, CAYMAN ISLANDS Panacea Innovation Limited By: /s/ James Huang, Founding Managing Partner 01 Dec 2025 0002010692
Huang James Director, 10%+ Owner C/O MAPLES CORPORATE SERVICES LIMITED,, UGLAND HOUSE, GRAND CAYMAN, CAYMAN ISLANDS /s/ James Huang 01 Dec 2025 0001573160

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction ATRA Common Stock Options Exercise $4.87 +48.7K $0.00 48.7K 28 Nov 2025 See Footnotes F1, F2
transaction ATRA Common Stock Tax liability -$14 -1 0% $14.03 48.7K 28 Nov 2025 See Footnotes F1, F2
holding ATRA Common Stock 1.41M 28 Nov 2025 See Footnotes F2, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction ATRA Warrants Options Exercise -$322K -48.7K -15.83% $6.61 259K 28 Nov 2025 Common Stock 48.7K $0.00 See Footnotes F1, F2, F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Represents securities held by Panacea Opportunity Fund I, L.P.
F2 James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.
F3 Represents securities held by Panacea Venture Healthcare Fund II, L.P.
F4 The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock.