SoundCloud, the music-sharing startup founded in 2007, may soon join the billion-dollar ranks of Snapchat and Uber.

According to The Wall Street Journal, the Berlin company is reportedly raising significant capital, in the ballpark of $150 million, at a valuation expected to top $1.2 billion. SoundCloud is also in discussions with major record labels to license songs, according to the Journal

SoundCloud has been within arm's reach of the Billion Dollar Club for a while now, but for the most part has played second fiddle in the media to deep-pocketed competitors such as Spotify, which raised $250 million late last year, and Beats Music, now owned by Apple. This despite the fact that SoundCloud's twist on streaming free music--with an emphasis on never-before-heard mixes--has won it plenty of fans. (It has also attracted plenty of critics because those mixes use songs SoundCloud hasn't officially licensed.)

SoundCloud has gained traction on both sides of the Atlantic, unlike other music startups in Europe. That's partly due to its celebrity appeal--Beyoncé is known to put rare and unreleased mixes on her page--and its appeal to users as a Spotify substitute, Matt Pincus, founder of music publishing company Songs Publishing, told Inc. in January (the same month SoundCloud raised about $60 million at a $700 million valuation.) 

Yet for all this appeal--SoundCloud says it attracts more than 175 million unique listeners each month, with content creators uploading about 12 hours worth of audio every minute, reports the Journal--it is still missing several key pieces that would ensure long-term survival.

For starters, SoundCloud lacks key agreements with big record labels like Sony Music Entertainment, which thus far have been wary about how the startup plans to monetize music used in mashups and mixes.

There is also no clear path to monetization for the people making the music. Despite the introduction of ads this year, SoundCloud has only shared revenue with about 60 "Premiere Partners," according to the Journal, including indie labels and artists selected on an invite-only basis. The rest of the content creators are out of luck and must pay fees as high as $135 per year to upload significant amounts of material.