---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-078933"
form_type: "8-K"
ticker: "CSTL"
cik: "0001447362"
company_name: "CASTLE BIOSCIENCES INC"
filed_at: "2024-03-27T23:59:59+00:00"
generated_at: "2026-06-04T07:05:17.874420+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Castle Biosciences secures $35M SVB loan facility; appoints Rodney Cotton to board

## Summary
- Entered Loan Agreement with Silicon Valley Bank for $10M drawn, $25M additional available.
- Proceeds to fund future HQ office building and working capital; interest at WSJ Prime +0.25% (floor 6%).
- Interest-only through Nov 2025 (extendable to Nov 2026); maturity Nov 2028; secured by most assets.
- Director Mara Aspinall not standing for re-election; Rodney Cotton (ex-Roche) appointed as Class II director.
- Cotton receives initial RSU valued at $350K vesting over 3 years plus annual $45K cash retainer.

## SEC filing metadata
- accession: 0001193125-24-078933
- form_type: 8-K
- ticker: CSTL
- cik: 0001447362
- company_name: CASTLE BIOSCIENCES INC
- filed_at: 2024-03-27T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 1.01, 5.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447362/000119312524078933/0001193125-24-078933-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447362/000119312524078933/d782226d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-078933
- JSON: https://secwatch.observer/filing/0001193125-24-078933.json
- Plain text: https://secwatch.observer/filing/0001193125-24-078933.txt

## Key facts
- Executive change
  Mara G. Aspinall departed as Director at CASTLE BIOSCIENCES INC.
  - Action: not to stand for re-election
  - Role: Director
  source text: On March 26, 2024, Mara G. Aspinall notified the Company that she will not to stand for re-election to the board of directors (the “Board”) of the Company at the expiration of her current term at the Company’s 2024 Annual Meeting of Stockholders (the “2024 Annual Meeting”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1447362/000119312524078933/0001193125-24-078933-index.htm
- Executive change
  Rodney Cotton was appointed as Class II Director at CASTLE BIOSCIENCES INC.
  - Action: appointed
  - Role: Class II Director
  source text: On March 26, 2024, following the recommendation of the nominating and corporate governance committee of the Board, the Board increased the size of the Board from eight to nine members and appointed Rodney Cotton to serve as a Class II director with a term ending at the 2024 Annual Meeting.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1447362/000119312524078933/0001193125-24-078933-index.htm
- Material Agreements
  CASTLE BIOSCIENCES INC entered into Loan and Security Agreement with Silicon Valley Bank, a division of First-Citizens Bank & Trust Company valued at $10.0 million aggregate principal amount of term loans (effective 2024-03-26).
  - Action: entry
  - Agreement: credit facility
  - Counterparty: Silicon Valley Bank, a division of First-Citizens Bank & Trust Company
  - Value: $10.0 million aggregate principal amount of term loans
  - Effective: 2024-03-26
  source text: On March 26, 2024 (the “Closing Date”), Castle Biosciences, Inc., a Delaware corporation (the “Company”), entered into a Loan and Security Agreement (the “Loan Agreement”), by and between the Company, its wholly owned subsidiary, Castle Narnia Real Estate Holding 1, LLC (“Narnia”) and Silicon Valley Bank, a division of First-Citizens Bank & Trust Company (the “Lender”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1447362/000119312524078933/0001193125-24-078933-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.