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Plantsea

5 known investors

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PlantSea develops seaweed-based packaging materials as an alternative to single-use plastics. It targets companies seeking eco-conscious packaging solutions.

Founders & leadership

RRRhiannon Rees
Rhiannon ReesCo-Founder & CEORhiannon Rees is co-founder and CEO of PlantSea, which develops seaweed-based packaging materials as an alternative to single-use plastics.
AN
Alex NewnessCo-Founder & COO

Investors · 5

Also in the syndicate · 1

Syndicate Room

Funding

SEC filings, press & company announcements

Source: company announcements and press reports — follow each round's link for the claim.

Companies House · registry record

View on Companies House ↗
Registered name
PLANTSEA LTD
Company number
12551709
Status
Active
Company type
Private limited company
Incorporated
8 Apr 2020
Registered office
Optic Technology Centre, St. Asaph Business Park, St. Asaph, LL17 0JD
Nature of business (SIC)
72110 — Research and experimental development on biotechnology
Accounts
last made up to 30 Apr 2025 · next due 31 Jan 2027
Confirmation statement
last made up to 7 Apr 2026 · next due 21 Apr 2027

Current officers · 3

  • Belinda Katharine Howell — director, appointed 20 Apr 2026
  • Alex Timothy Newnes — director, appointed 8 Apr 2020
  • Rhiannon Lynne Rees — director, appointed 8 Apr 2020

Source: Companies House public register · retrieved 16 Aug 2026. Contains public sector information licensed under the Open Government Licence v3.0.

Frequently asked questions

What does Plantsea do?
PlantSea develops seaweed-based packaging materials as an alternative to single-use plastics. It targets companies seeking eco-conscious packaging solutions.
Who founded Plantsea?
Plantsea was founded by Rhiannon Rees, Alex Newness.
Who are Plantsea's investors?
Plantsea's investors include Sustainable Ventures, SFC Capital, Angels Invest Wales, Innovate UK.