Shares of T-Mobile US (TMUS) enjoyed a modest bounce Thursday morning amid reports that Japan’s SoftBank is huddling with bankers over financing a possible $20 billion bid to acquire the No. 4 U.S. wireless provider.

The reports adds to the signs that one or more players may be preparing to make a move on T-Mobile, which is majority owned by Deutsche Telekom.

According to Reuters, SoftBank, which recently acquired majority control of Sprint (S), is in talks to buy T-Mobile as well as discussions with banks about cobbling together financing.

Other reports indicate SoftBank has had talks with banks including Credit Suisse (CS), Mizuho Bank, Goldman Sachs (GS) and Deutsche Bank (DB).

Softbank and T-Mobile did not respond to requests for comment, while Sprint declined to comment. 

A deal for T-Mobile would allow the Tokyo-based company to vault over Verizon Communications (VZ) and AT&T (T) to become the world’s No. 2 mobile carrier by revenue, Reuters reported.

However, a combination of Sprint and T-Mobile likely faces serious hurdles.

First, antitrust regulators may frown upon a tie-up between the No. 3 and No. 4 U.S. wireless providers, fearing it limits competition. U.S. regulators shot down AT&T’s $39 billion effort to acquire T-Mobile in 2011.

Also, other bidders may emerge. Dish Network (DISH) is reportedly sizing up T-Mobile as a takeover candidate and has talked to Deutsche Telekom about a possible deal.

Thanks to all the M&A buzz, shares of T-Mobile ticked up 1.19% to $32.57 Thursday morning. The rally leaves the stock up almost 64% this year. 

Follow Matt Egan on Twitter @MattMEgan5