Shares of utility PG&E popped 37.5 percent on Friday after the head of a regulator eased worries about the California-based utility going bankrupt. Friday's rise marks the stock's biggest in at least four decades.
In a call with Wall Street analysts, California Public Utilities Commission head Michael Picker reportedly said he could not imagine letting PG&E go bankrupt as it faces billions of dollars in potential liability from the wildfires ravaging California. Picker's comments on the call were first reported by Bloomberg News.
Picker later told the San Francisco Chronicle that the agency would implement a provision through which utilities can pass wildfire costs on to consumers.
"Why is the CPUC stepping up now vs. mostly looking for legislative initiatives earlier? Given the reaction in the stock market, we think there was an appropriate level of urgency that something needed to be done," an analyst at Citi Research wrote in a note Friday. The analyst also upgraded the stock to buy from neutral.
"We also think the CPUC is stepping up now because it is easier for them to come out quickly to support the utility vs. something from the political spectrum," the note said.
PG&E's stock had sunk more than 50 percent for the week entering Friday's session amid concerns that its equipment could be partly responsible for the so-called Camp Fire raging in Northern California. The stock ended the week down 38.9 percent.
The Wall Street exodus from the utility began in earnest Wednesday after the company said that, if its equipment is found responsible for the fire, the costs would exceed its insurance coverage and impact its financial well-being.
PG&E said in an email that it's "not going to speculate or comment on what factors may or may not be impacting the stock market."
Though the cause of the Camp Fire remains under investigation, the utility company also said that it submitted an "electric incident report" to the California Public Utilities Commission on Nov. 8, just before the wildfire. The report indicated a power failure on a transmission line in Butte County at 6:15 a.m. PST that day. The fire was reported at approximately 6:30 a.m. PST, according to state records.
NBC News reported late Wednesday that at least 63 people have died from the Camp Fire. It is the deadliest wildfire in the state's history.
— CNBC's Michael Bloom contributed to this report.