Companies would have to disclose publicly whether they have anyone on their board who is a "cybersecurity expert" under legislation introduced in the U.S. Senate on Thursday.

The outlook for approval of this proposal was unclear, but it comes at a time of growing concern in Congress about damaging computer hacks that have hit companies such as Target, Anthem Insurance Companies Inc and Home Depot.

The measure, from Republican Senator Susan Collins of Maine and Democratic Senator Jack Reed of Rhode Island, would require the disclosure in companies' filings with the U.S. Securities and Exchange Commission.

It would not require companies to take any action beyond disclosure. Companies lacking a cybersecurity expert would have to explain themselves and say what other steps they are taking to improve their cybersecurity.

The bill would require the SEC and the National Institute of Standards and Technology to provide guidance on the minimum qualifications for what is considered a cybersecurity expert.

A separate cybersecurity proposal was tucked into a massive federal spending bill released on Wednesday.

That measure aims to cajole the private sector into sharing more cyber threat data with the government by expanding company liability protections, an arrangement intended to improve hack detection and prevention.