| Date | Name | Symbol | Type | Security | Shares | Price | Value | Ownership | Reported |
| 06/08/2023 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | Common Stock | 2.3k | $0.00 | $0 | | 06/08/2023 |
| 06/08/2023 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | | 14k | $8.13 | $113.4k | | 06/08/2023 |
| 05/15/2023 | Y-mAbs Therapeutics, Inc. | YMAB | Purchase | Common Stock | 101.7k | $9.65 | $981.4k | By WG Biotech ApS | 05/15/2023 |
| 07/15/2022 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | | 16k | $16.64 | $266.2k | | 07/15/2022 |
| 06/10/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 11.2k | $36.15 | $406k | By WG Biotech ApS | 06/10/2021 |
| 06/10/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | | 16k | $37.53 | $600.5k | | 06/10/2021 |
| 06/09/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 116.7k | $36.19 | $4.2M | By WG Biotech ApS | 06/08/2021 |
| 06/08/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 33.3k | $35.28 | $1.2M | By WG Biotech ApS | 06/08/2021 |
| 06/07/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 72.4k | $34.15 | $2.5M | By WG Biotech ApS | 06/07/2021 |
| 06/04/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 3.8k | $34.03 | $130.7k | By WG Biotech ApS | 06/03/2021 |
| 06/03/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 30.7k | $33.19 | $1M | By WG Biotech ApS | 06/03/2021 |
| 06/01/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 6.9k | $35.57 | $244.2k | By WG Biotech ApS | 05/28/2021 |
| 05/28/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 25k | $36.34 | $908.5k | By WG Biotech ApS | 05/28/2021 |
| 03/10/2021 | Y-mAbs Therapeutics, Inc. | YMAB | Other (disposition) | Common Stock | 1M | $0.00 | $0 | By WG Biotech ApS | 03/10/2021 |
| 06/23/2020 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | | 16k | $48.67 | $778.7k | | 06/23/2020 |
| 12/30/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Other (acquisition) | Common Stock | 498.4k | $0.00 | $0 | By WG Biotech ApS | 12/30/2019 |
| 12/30/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Other (disposition) | Common Stock | 498.4k | $0.00 | $0 | By Weco Group A/S | 12/30/2019 |
| 09/06/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 5.8k | $27.00 | $156.4k | By Weco Group A/S | 09/05/2019 |
| 09/05/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 11.5k | $27.00 | $309.2k | By Weco Group A/S | 09/05/2019 |
| 08/30/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 100 | $27.00 | $2.7k | By Weco Group A/S | 08/29/2019 |
| 08/29/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 89.1k | $26.58 | $2.4M | By Weco Group A/S | 08/29/2019 |
| 08/28/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 29.6k | $27.02 | $798.5k | By Weco Group A/S | 08/27/2019 |
| 08/27/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 19.8k | $27.18 | $538.3k | By Weco Group A/S | 08/27/2019 |
| 08/22/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 990 | $27.75 | $27.5k | By Weco Group A/S | 08/22/2019 |
| 08/21/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 60.1k | $27.83 | $1.7M | By Weco Group A | 08/20/2019 |
| 08/21/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 60.1k | $27.83 | $1.7M | By Weco Group A/S | 08/20/2019 |
| 08/20/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 108.1k | $27.42 | $3M | By Weco Group A/S | 08/20/2019 |
| 08/20/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Sale | Common Stock | 108.1k | $27.42 | $3M | By Weco Group A/S | 08/20/2019 |
| 07/15/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Other (disposition) | Common Stock | 860.1k | $0.00 | $0 | By Weco Group A/S | 07/15/2019 |
| 07/15/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Other (disposition) | Common Stock | 860.1k | $0.00 | $0 | By Weco Group A/S | 07/15/2019 |
| 06/12/2019 | Y-mAbs Therapeutics, Inc. | YMAB | Grant | | 16k | $21.45 | $343.2k | | 06/12/2019 |