Dan Frommer, Business Insider
No deal has been finalized and Twitter is just one acquisition route that Circa is exploring, the sources said.
It's unclear what Circa's valuation is; the startup has raised nearly $6 million since its 2011 launch.
Circa, which produces brief news stories for mobile devices, was founded by Matt Galligan. It has a long list of early-stage investors including Path CEO David Morin, Wordpress founder Matt Mullenweg, and Quotidian Ventures.
Fortune's Dan Primack previously reported that Circa was seeking an acquirer after an $8 million funding round fell through. Galligan declined to comment about specific conversations with Twitter but says that he has been exploring exit opportunities for his application.
The application lacks significant scale, and it may be more powerful in partnership with a larger company than as a standalone startup.
"We didn't put Circa up for sale,'" Galligan tells Business Insider. "We've got a term sheet for a Series A on the table, but after evaluating all the inbound interest from potential acquiring parties, we decided we wanted to give more attention to those conversations."
If Circa gets acquired, it will be the latest media startup to get consolidated. Earlier this year, popular tech publication Gigaom unexpectedly went out of business.
There are a number of media startups that have raised money from venture capitalists in the past few years, and many of them are expected to either get gobbled up by larger companies or run out of money in the next few months.
It's a little unusual that Twitter would want to acquire a media startup. Twitter doesn't currently produce any of its own content. Instead, it helps its users - many of which are publishers and media organizations - spread their content and links to followers.
Twitter declined to comment for this story.
Actually, Twitter would be wise to buy @circa. Add native tweet, RT, Vine, and Periscope integration and you've got @benthompson's news app.
- Zach Kahn (@zkahn94) April 30, 2015