Form 13-F position report

BIOATLA INC

Reported by SIMPLEX TRADING LLC

BCAB CUSIP 09077B104 Manager CIK 0001488542

Reported 120,391 shares, up 84,235 (233.0%) from the prior quarter.

Reported value 184.9%; share count 233.0% vs. the prior quarter.

Added
% of reported 13F value < 0.01% This manager · Q4 2025
Shares 120,391 Quarter-end amount reported
Reported value $68,382 Fair value at quarter end
Consecutive quarters held 17 Through Q4 2025

Reported position value by quarter

Reported position value by quarter

Each bar is a Form 13-F quarter-end snapshot. It does not show trades made within the quarter.

Reported position value by quarter
Date Holding Value
2021-12-31 167000
2022-03-31 56000
2022-06-30 66000
2022-09-30 17000
2022-12-31 89000
2023-03-31 4000
2023-06-30 0
2023-09-30 63000
2023-12-31 29000
2024-03-31 148000
2024-06-30 0
2024-09-30 50000
2024-12-31 0
2025-03-31 3000
2025-06-30 5000
2025-09-30 24000
2025-12-31 68382
2026-03-31 11898
2026-06-30 0

Quarterly position history

How this manager's reported quarter-end position changed over time.

19 quarters
Quarterly reported position history for BIOATLA INC held by SIMPLEX TRADING LLC.
Quarter Activity Shares Change % of reported 13F Reported value Filed Source filing
Q2 2026 Reduced 0 -73,901 (-100.0%) 0 $0 2026-08-12
Q1 2026 Reduced 73,901 -46,490 (-38.6%) < 0.01% $11,898 2026-05-14
Q4 2025 Added 120,391 +84,235 (233.0%) < 0.01% $68,382 2026-02-11
Q3 2025 Added 36,156 +22,858 (171.9%) < 0.01% $24,000 2025-11-12
Q2 2025 Added 13,298 +3,835 (40.5%) < 0.01% $5,000 2025-08-05
Q1 2025 New 9,463 +9,463 (0.0%) < 0.01% $3,000 2025-05-12
Q4 2024 Reduced 0 -28,490 (-100.0%) 0 $0 2025-02-11
Q3 2024 New 28,490 +28,490 (0.0%) < 0.01% $50,000 2024-11-08
Q2 2024 Reduced 0 -43,239 (-100.0%) 0 $0 2024-07-25
Q1 2024 Added 43,239 +31,313 (262.6%) < 0.01% $148,000 2024-04-25
Q4 2023 Reduced 11,926 -25,575 (-68.2%) < 0.01% $29,000 2024-02-02
Q3 2023 New 37,501 +37,501 (0.0%) < 0.01% $63,000 2023-11-01
Q2 2023 Reduced 0 -1,858 (-100.0%) 0 $0 2023-08-04
Q1 2023 Reduced 1,858 -8,966 (-82.8%) < 0.01% $4,000 2023-04-27
Q4 2022 Added 10,824 +8,565 (379.2%) < 0.01% $89,000 2023-02-02
Q3 2022 Reduced 2,259 -21,212 (-90.4%) < 0.01% $17,000 2022-11-04
Q2 2022 Added 23,471 +12,215 (108.5%) < 0.01% $66,000 2022-08-03
Q1 2022 Added 11,256 +2,703 (31.6%) < 0.01% $56,000 2022-05-02
Q4 2021 New 8,553 +8,553 (0.0%) < 0.01% $167,000 2022-02-04

Who else reported the position

48 managers reported BIOATLA INC for Q4 2025.

Managers reporting BIOATLA INC in Q4 2025.
Manager Activity Shares Change % of reported 13F Reported value Tenure
ACORN CAPITAL ADVISORS LLC Unchanged 4,835,111 0 0.93% $2,756,013 5 qtrs
VANGUARD GROUP INC Unchanged 1,945,795 0 < 0.01% $1,105,212 21 qtrs
MARSHALL WACE LLP New 891,580 +891,580 < 0.01% $508,201 6 qtrs
MILLENNIUM MANAGEMENT LLC Added 762,394 +421,072 < 0.01% $432,811 21 qtrs
ACADIAN ASSET MANAGEMENT LLC Reduced 757,671 -172,791 < 0.01% $429,000 9 qtrs
RENAISSANCE TECHNOLOGIES LLC Reduced 707,214 -93,417 < 0.01% $401,485 17 qtrs
DEUTSCHE BANK AG Unchanged 525,353 0 < 0.01% $299,451 20 qtrs
GEODE CAPITAL MANAGEMENT LLC Added 500,328 +5,117 < 0.01% $284,096 21 qtrs
BlackRock Inc Unchanged 480,933 0 < 0.01% $273,026 6 qtrs
JANE STREET GROUP LLC Added 346,774 +152,397 < 0.01% $196,863 20 qtrs
Premium adds each manager's conviction percentile across reporting peers.
Filing details and methodology As reported
Report period
December 31, 2025
Filed
February 11, 2026
Filing type
13F-HR
Position type
COM

Voting authority reported

Sole
120,391
Shared
0
None
0

“None” means the manager reported no voting authority for those shares on non-routine matters. It does not disclose why and is not evidence of securities lending.

Form 13-F is a delayed quarter-end snapshot of disclosed long Section 13(f) securities. It can be filed up to 45 days after quarter end, excludes short positions and most non-U.S. securities, and does not reveal intra-quarter trading. For options, reported shares and value describe the underlying-share exposure; strike, expiry, premium, and written positions are not disclosed.