Stock-based Compensation (FY) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2024

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

The following table sets forth the summary of options activity, under the 2018 Plan and the 2021 Plans, for the nine months ended September 30, 2024:

(in thousands, except share-based data)

Total

Options

Weighted-Average

Exercise Price Per

Weighted-Average

Remaining Contractual

Term (In Years)

Aggregate

Intrinsic

Value

Outstanding as of December 31, 2023

23,912

$68.39


(in thousands, except share-based data)	Total Options	Weighted-Average Exercise Price Per Share	Weighted-Average Remaining Contractual Term (In Years)	Aggregate Intrinsic Value
Forfeitures	(4,502)	11.96
Outstanding as of September 30, 2024	19,410	$81.48	6.6	$—
Exercisable as of September 30, 2024	17,478	$76.44	6.5	$—
Vested and expected to vest as of September 30, 2024	19,410	$81.48	6.6	$—

The following table sets forth the summary of options activity, under the 2018 Plan and the 2021 Plans, for the year ended December 31, 2023:


(in thousands, except share-based data)	Total Options	Weighted-Average Exercise Price Per Share	Weighted-Average Remaining Contractual Term (In Years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2022	51,166	$60.69
Vested exercised	(10,081)	$12.95
Forfeitures	(17,173)	$77.95
Outstanding as of December 31, 2023	23,912	$68.39	7.1	$—
Exercisable as of December 31, 2023	18,705	$54.36	6.8	$—


(in thousands, except share-based data)	Total Options	Weighted-Average Exercise Price Per Share	Weighted-Average Remaining Contractual Term (In Years)	Aggregate Intrinsic Value
Vested and expected to vest as of December 31, 2023	23,912	$68.39	7.1	$—

Schedule of Restricted Stock Unit and Restricted Stock Award Activity

The following table sets forth the summary of RSU and RSA activity, under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan, for the nine months ended September 30, 2024. RSAs were an immaterial portion of activity for the period:


	Shares	Weighted Average Grant Date Fair Value (i.e. Share Price)
Outstanding as of December 31, 2023	219,720	$86.78
Vested	(36,570)	67.15
Forfeited	(73,718)	47.72
Outstanding as of September 30, 2024	109,432	$119.66

The following table sets forth the summary of RSU and RSA activity, under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan, for the year ended December 31, 2023. RSAs were an immaterial portion of activity for the period:


	Shares	Weighted Average Grant Date Fair Value (i.e. Share Price)
Outstanding as of December 31, 2022	155,573	$199.74
Granted	212,089	27.26
Vested	(42,701)	202.28
Forfeited	(105,241)	86.95
Outstanding as of December 31, 2023	219,720	$86.78

Schedule of Stock-Based Compensation Expense

The following table sets forth the stock-based compensation under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan by expense type:


	Three Months Ended September 30,		Nine Months Ended September 30,
(in thousands)	2024	2023	2024	2023
Research and development expenses	$275	$472	$499	$1,629
Selling, general and administrative expenses	1,432	1,684	4,386	4,824
Total	$1,707	$2,156	$4,885	$6,453

The following table sets forth the stock-based compensation under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan by award type:


	Three Months Ended September 30,		Nine Months Ended September 30,
(in thousands)	2024	2023	2024	2023
Options	$71	$81	$216	$269
RSUs & RSAs	1,636	2,068	4,669	6,167
ESPP	—	7	—	17
Total	$1,707	$2,156	$4,885	$6,453

The following table sets forth the stock-based compensation under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan by expense type:


	Year Ended December 31,
(in thousands)	2023	2022
Research and development expenses	$2,131	$2,134
Selling, general and administrative expenses	6,349	9,446
Total	$8,480	$11,580

The following table sets forth the stock-based compensation under the Initial Plan, the 2018 Plan, the 2021 Plan, and the 2022 Plan by award type:


	Year Ended December 31,
(in thousands)	2023	2022
Options	$352	$538
RSUs & RSAs	8,115	10,995
ESPP	13	117
Performance Awards	—	(70)
Total	$8,480	$11,580