Workers’ Compensation · Primary-source case analysis

Vargas: New Apportionment Law Applied to Increased Disability on Reopening

By Aneeta Mishra and Timothy Chan

Published April 28, 2026

Vargas separates the protected finality of an original award from the law governing a later claim of new and further permanent disability.

A petition to reopen was pending when the law changed

Myrtle Vargas sought increased permanent disability within the statutory reopening period. Senate Bill 899 took effect while that claim remained unresolved.

New apportionment rules governed the increase

The Board applied the causation provisions to the issue of increased disability in a petition pending on April 19, 2004, regardless of the original injury date.

The final original award remained intact

The new law could not be used to recalculate the level of disability or apportionment fixed in a final pre-amendment award. The inquiry concerned only the claimed increase.

Disposition

The WCAB denied removal and directed that increased disability be determined under the new apportionment rules without reference to how the original award handled apportionment.

Key takeaways

• Separate original disability from the claimed increase.
• Confirm when the original award became final.
• Apply the law governing the pending reopening issue.
• Do not relitigate findings protected by finality.