SPRO Shares Outstanding - Spero Therapeutics, Inc.

Complete source-backed shares outstanding history.

Available history: 2016-12-31 to 2026-08-07
Data captured: 2026-09-04

Historical Shares Outstanding

Date	Shares outstanding
2026-08-07	58,234,827
2026-06-30	58,146,910
2026-05-01	57,901,493
2026-03-31	57,891,493
2026-03-20	57,891,493
2025-12-31	56,414,657
2025-11-06	56,339,295
2025-09-30	56,311,795
2025-08-05	56,275,225
2025-06-30	56,187,308
2025-05-01	55,910,641
2025-03-31	55,900,641
2025-03-21	55,900,641
2024-12-31	54,593,527
2024-11-06	54,518,165
2024-09-30	54,314,415
2024-08-01	54,049,139
2024-06-30	54,009,139
2024-05-06	53,986,639
2024-03-31	53,869,139
2024-03-08	53,869,139
2023-12-31	52,999,680
2023-11-06	52,999,317
2023-09-30	52,999,317
2023-08-04	52,696,289
2023-06-30	52,571,813
2023-05-01	52,571,813
2023-03-31	52,571,813
2023-03-01	52,571,813
2022-12-31	52,456,195
2022-11-10	51,776,053
2022-09-30	42,856,623
2022-08-05	35,067,477
2022-06-30	35,067,477
2022-05-12	32,821,544
2022-03-31	32,755,559
2022-03-25	32,755,559
2021-12-31	32,393,738
2021-11-05	32,323,617
2021-09-30	32,220,351
2021-07-29	32,146,847
2021-06-30	29,699,147
2021-04-29	29,665,165
2021-03-31	29,663,946
2021-03-08	29,504,257
2020-12-31	29,260,247
2020-10-29	27,187,489
2020-09-30	25,970,105
2020-07-30	21,152,541
2020-06-30	21,014,095
2020-05-01	20,595,288
2020-03-31	20,328,340
2020-03-09	20,328,340
2019-12-31	19,190,695
2019-10-31	19,128,146
2019-09-30	18,663,030
2019-08-05	18,656,200
2019-06-30	18,650,375
2019-05-06	17,523,835
2019-03-31	17,335,066
2019-03-08	17,215,976
2018-12-31	17,205,962
2018-11-05	18,187,488
2018-09-30	18,182,494
2018-08-06	18,168,429
2018-06-30	14,377,753
2018-05-07	14,377,753
2018-03-31	14,369,182
2018-03-28	14,369,182
2017-12-31	14,369,182
2017-11-30	14,369,182
2017-09-30	335,281
2016-12-31	0