# Montana SB 473: Prohibit weather modification.

Montana SB 473, Prohibit weather modification., is a 69th Legislature, Regular Session (2025) Senate bill sponsored by Bob Phalen (Republican); status failed, last action 2025-05-23 (Died in Process) (as of 2026-10-16).

- Canonical: https://policyrisk.com/state-bill/MT-SB473-2025
- As of: 2026-10-16
- Plain-text twin of the page above; the HTML and this file carry the same facts.

## Facts
- Bill: Montana SB 473
- State: Montana
- Session: 69th Legislature, Regular Session (2025)
- Title: Prohibit weather modification.
- Status: failed
- Chamber: Senate
- Introduced: 2025-02-25
- Last action: 2025-05-23, Died in Process
- Sponsor: Bob Phalen (Republican)
- Cosponsors: 0
- Subjects: Transportation
- Touches household money: no
- Roll calls: 7 (223 yes, 176 no in all)
- Economic provisions PRIA read: 0

## Summary

No summary available.

## Bill overview

No economic impacts identified for this bill.

## Sponsors and cosponsors

- Sponsor: Bob Phalen (Republican), Senate

## Roll call votes

| Date | Chamber | Motion | Result | Yes | No | Other |
| --- | --- | --- | --- | --- | --- | --- |
| 2025-04-10 | House | Do Concur | fail | 45 | 55 |   |
| 2025-03-06 | Senate | Do Pass | pass | 34 | 15 |   |
| 2025-03-06 | Senate | Do Pass | pass | 34 | 16 |   |
| 2025-03-05 | Senate | AMD-SB0473.001.001 Usher D/PASS | pass | 30 | 20 |   |
| 2025-03-05 | Senate | ReconsAction and place on Second Reading on 3/6/2025 -Hertz | pass | 29 | 21 |   |
| 2025-03-05 | Senate | Do Pass As Amended | fail | 24 | 26 |   |
| 2025-03-05 | Senate | Indefinitely Postpone -McGillvray | pass | 27 | 23 |   |

## Actions (20)

- 2025-05-23: Died in Process (Senate)
- 2025-04-10: 2nd Reading (House)
- 2025-04-08: Committee Report (House)
- 2025-04-07: Committee Executive Action (House)
- 2025-03-24: Hearing (House)
- 2025-03-17: 1st Reading (House)
- 2025-03-17: Referred to Committee (House)
- 2025-03-07: Transmitted to House (Senate)
- 2025-03-06: 3rd Reading (Senate)
- 2025-03-06: 2nd Reading (Senate)
- 2025-03-05: Reconsidered Previous Action (Senate)
- 2025-03-05: 2nd Reading Indefinitely Postponed (Senate)
- 2025-03-05: 2nd Reading (Senate)
- 2025-03-05: 2nd Reading Motion to Amend (Senate)
- 2025-03-04: Committee Report (Senate)
- 2025-03-03: Committee Executive Action (Senate)
- 2025-02-28: Hearing (Senate)
- 2025-02-25: Referred to Committee (Senate)
- 2025-02-25: 1st Reading (Senate)
- 2025-02-25: Introduced (Senate)

## Bill text

- As Amended (Version 2), 2025-04-08: [PDF](https://docs.legmt.gov/download-ticket?ticketId=b395ea01-969e-4512-86c4-194e881f8004)
- Introduced, 2025-02-25: [PDF](https://docs.legmt.gov/download-ticket?ticketId=6edeb9bf-24e6-49f9-841d-b197ef563904)

## Related bills

- SB 437: Revise definition of sex in Montana law (signed)
- HB 831: Increase elderly homeowner and renter income tax credit (vetoed)
- HB 628: Revise early literacy targeted intervention laws (vetoed)
- SB 410: Provide for Montana genomic security act (vetoed)
- SB 424: Revising the disabled veteran property tax assistance program (vetoed)
- SB 422: Generally revise laws relating to insurance coverage relating to cancer (vetoed)

## Sources
- [As Amended (Version 2) (PDF)](https://docs.legmt.gov/download-ticket?ticketId=b395ea01-969e-4512-86c4-194e881f8004)
- [Introduced (PDF)](https://docs.legmt.gov/download-ticket?ticketId=6edeb9bf-24e6-49f9-841d-b197ef563904)

## Related
- [SB 437: Revise definition of sex in Montana law](https://policyrisk.com/state-bill/MT-SB437-2025)
- [HB 831: Increase elderly homeowner and renter income tax credit](https://policyrisk.com/state-bill/MT-HB831-2025)
- [HB 628: Revise early literacy targeted intervention laws](https://policyrisk.com/state-bill/MT-HB628-2025)
- [SB 410: Provide for Montana genomic security act](https://policyrisk.com/state-bill/MT-SB410-2025)
- [SB 424: Revising the disabled veteran property tax assistance program](https://policyrisk.com/state-bill/MT-SB424-2025)
- [SB 422: Generally revise laws relating to insurance coverage relating to cancer](https://policyrisk.com/state-bill/MT-SB422-2025)
- [Montana bills](https://policyrisk.com/states/montana/bills)
- [Montana state hub](https://policyrisk.com/states/montana)
- [All state legislation](https://policyrisk.com/state-bills)

Source: PRIA, https://policyrisk.com/state-bill/MT-SB473-2025 (as of 2026-10-16).