Welcome to Law.com Class Actions: Critical Mass, a weekly briefing for class action and mass tort attorneys.

This week: On Monday, a bankruptcy judge in Texas froze all talc litigation at the first hearing in Johnson & Johnson's latest Chapter 11 case. A Chicago jury on Sept. 18 failed to reach a verdict in a Zantac case. Nearly a dozen law firms are involved in litigation over the March 26 collapse of the Francis Scott Key Bridge.