The owner of Hardee’s and Carl’s Jr. hamburger chains said it has received a new takeover offer that has no evidence of committed financing and is subject to several conditions. Still, fast-food investors scarfed down CKE shares on the news.

In February, CKE agreed to be bought by private equity firm Thomas H. Lee Partners for $619 million cash. It had until Tuesday to shop for other offers. That’s when Porter Orlin, a New York-based investment manager holding a chunk of CKE shares, piped up with a letter saying he was opposed to the deal because it undervalued the business.

The company posted a six-fold jump in quarterly profit in March that beat market expectations, as it cut costs and got a tax boost. The figures covered a tough first few months for the industry, when bad weather and high unemployment hit sales.

If the new bidder gets bold enough to go public in its move to unseat the private equity buyers, could hunger for fast food become a theme of the M&A recovery?