Privacy concerns have delayed a U.S. Senate vote on a controversial cyberthreat information-sharing bill until lawmakers return from a month-long recess.

The Senate will not vote on the Cybersecurity Information Sharing Act (CISA) before lawmakers leave Washington, D.C., Thursday for their August recess, Senate Majority Leader Mitch McConnell said late Wednesday.

CISA would give businesses immunity from customer lawsuits when they share information about cyberthreats with each other and with federal agencies, but opponents of the bill say it would enable the sharing of personal information with the National Security Agency and other intelligence agencies.

McConnell, a Kentucky Republican, had pushed this week for a cloture vote, which would have ended debate and set up a final vote on CISA. But several senators objected to the legislation and pushed for several amendments.

Under an agreement between majority Republicans and minority Democrats, opponents of the legislation have withdrawn their insistence that the Senate hold a cloture vote before moving to a final vote. Cloture requires a 60-vote supermajority of the 100-member Senate.

In return, McConnell will allow about 20 amendments to CISA to be introduced when the bill comes back to the Senate for a vote this fall.

Digital rights groups and other opponents of CISA had waged an aggressive campaign against CISA in recent weeks, with opponents sending more than 6 million faxes to senators in less than a week.

On the other side, several trade groups, including the tech-focused Information Technology Industry Council [ITI], have called on the Senate to pass the bill.

Without amendments, CISA would have allow agencies to share customer information with government agencies with “only a cursory review,” Senator Ron Wyden, an Oregon Democrat and opponent of the bill said Wednesday.

“Information sharing ... without vigorous, robust privacy safeguards will not be considered by millions of Americans to be a cybersecurity bill,” Wyden added. “Millions of Americans will say that legislation is a surveillance bill.”

Supporters of CISA say the bill makes information sharing by businesses voluntary, “but for the citizens of Pennsylvania and the citizens of Oregon, it’s not voluntary,” Wyden said. “The people of Pennsylvania won’t be asked first whether they want their information sent to the government. For them, this legislation is mandatory.”

Others called on the Senate to pass CISA. Cyberattacks against the U.S. are “getting more and more devastating,” said Senator Dianne Feinstein, a California Democrat. “It isn’t going to stop. It’s going to get worse.”

Increased information sharing will help businesses identify and respond to cyberthreats, Feinstein added. CISA is “the on-ramp to cybersecurity protection in this country,” she said. “It gives companies the ability to talk to each other about a well-defined threat indicator.”