13D Filings
MoonLake Immunotherapeutics
MLTX
Amendment
Ownership

27.70%

Total Shares

19,751,284

Issuer CIK

1821586

CUSIP

61559X104

Event Date

Nov 5, 2025

Accepted

Nov 10, 2025, 05:27 PM

Reporting Persons (11)
Joint Filing

This is a joint filing. The reported shares may overlap between reporting persons and should not be summed.

NameType% of ClassAggregateSole VotingShared Voting
BVF INC/IL
CO
27.70%19,751,284019,751,284
LAMPERT MARK N
Individual
27.70%19,751,284019,751,284
BVF PARTNERS L P/IL
Investment Adviser
27.70%19,751,284019,751,284
BVF GP HOLDINGS LLC
Other
25.80%18,403,927018,403,927
BVF I GP LLC
Other
14.30%10,235,089010,235,089
BIOTECHNOLOGY VALUE FUND L P
Partnership
14.30%10,235,089010,235,089
BVF II GP LLC
Other
11.40%8,168,83808,168,838
BIOTECHNOLOGY VALUE FUND II LP
Partnership
11.40%8,168,83808,168,838
BVF Partners OS Ltd.
CO
1.80%1,287,76801,287,768
Biotechnology Value Trading Fund OS LP
Partnership
1.80%1,287,76801,287,768
Loy Spike
Individual
0.03%18,98518,9850
Disclosure Items (3)

Security Title

Class A ordinary share, par value $0.0001 per share

Issuer Name

MoonLake Immunotherapeutics

Issuer Address

DORFSTRASSE 29, ZUG, V8, 6300

Percentage of Class

Item 5(a) is hereby amended and restated to read as follows: The aggregate percentage of Shares reported owned by each person named herein is based on 71,373,579 Shares outstanding as of November 6, 2025, which is the total number of Shares outstanding following the closing of the Issuer's offering as reported in the Issuer's Prospectus Supplement filed with the Securities and Exchange Commission on November 5, 2025.

Number of Shares

Item 5(b) is hereby amended and restated to read as follows: As of the date hereof, (i) BVF beneficially owned 10,235,089 Shares, representing percentage ownership of approximately 14.3% of the Shares outstanding, (ii) BVF2 beneficially owned 8,168,838 Shares, representing percentage ownership of approximately 11.4% of the Shares outstanding, (iii) Trading Fund OS beneficially owned 1,287,768 Shares, representing percentage ownership of approximately 1.8% of the Shares outstanding, and (iv) 59,589 Shares were held in the Partners Managed Account, representing percentage ownership of less than 1% of the Shares outstanding. BVF GP, as the general partner of BVF, may be deemed to beneficially own the 10,235,089 Shares beneficially owned by BVF, representing percentage ownership of approximately 14.3% of the Shares outstanding. BVF2 GP, as the general partner of BVF2, may be deemed to beneficially own the 8,168,838 Shares beneficially owned by BVF2, representing percentage ownership of approximately 11.4% of the Shares outstanding. Partners OS, as the general partner of Trading Fund OS, may be deemed to beneficially own the 1,287,768 Shares beneficially owned by Trading Fund OS, representing percentage ownership of approximately 1.8% of the Shares outstanding. BVF GPH, as the sole member of each of BVF GP and BVF2 GP, may be deemed to beneficially own the 18,403,927 Shares beneficially owned in the aggregate by BVF and BVF2, representing percentage ownership of approximately 25.8% of the Shares outstanding. Partners, as the investment manager of BVF, BVF2, Trading Fund OS and the Partners Managed Account and the sole member of Partners OS, may be deemed to beneficially own the 19,751,284 Shares beneficially owned in the aggregate by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account, representing percentage ownership of approximately 27.7% of the Shares outstanding. BVF Inc., as the general partner of Partners, may be deemed to beneficially own the 19,751,284 Shares beneficially owned by Partners, representing percentage ownership of approximately 27.7% of the Shares outstanding. Mr. Lampert, as a director and officer of BVF Inc., may be deemed to beneficially own the 19,751,284 Shares beneficially owned by BVF Inc., representing percentage ownership of approximately 27.7% of the Shares outstanding. As of the date hereof, Mr. Loy beneficially owned 18,985 Shares, which consist of Shares issuable upon the exercise of certain options that are exercisable within sixty days hereof, representing percentage ownership of less than 1%.

Transactions

Item 5(c) is hereby amended and restated to read as follows: The Reporting Persons have not entered into any transactions in the securities of the Issuer during the past sixty days.

Item 6 is hereby amended to add the following: On June 5, 2025, Mr. Loy was granted stock options in connection with his service as a director of the Issuer that represent a right to purchase 6,682 Shares. Such options (a) will vest in full on the earlier of (i) June 5, 2026 and (ii) the date of the Issuer's next annual general meeting of shareholders, subject to Mr. Loy's continued service to the Issuer, (b) have an exercise price of $48.83 per Share and (c) expire on June 5, 2035.

MoonLake Immunotherapeutics — Schedule 13D | 13D Filings