How has Rap Genius distinguished itself from all the other lyrics sites? With sweet, sweet old school spam techniques, or as Silicon Valley likes to call it "growth hacking." The tactic is so shady that Matt Cutts, Google's head of search spam, felt compelled to publicly state that his team is "aware and looking into it."

Yesterday John Marbach, a former Thiel Fellow and Y Combinator alum, posted an email on his blog from Rap Genius cofounder Mahbod Moghadam. Yes, that joker. Marbach reached out to the company about the "Rap Genius Blog Affiliate" program they promoted on Facebook.

In response, Moghadam gave away their big secret. He instructed Marbach to embed links to the Rap Genius pages for Justin Bieber's new album in the bottom of one of his post, guaranteeing "MASSIVE traffic." Embed those links, Moghadam assured him, and your post "will bloooowwwww up!"

The chance that Marbach—who pitched Thiel on an education startup, but founded an email filtering service—would write a blog post relevant to Justin Bieber's new album is miniscule. Rap Genius is well aware of that. They're just in it for the SERP, Marbach explains:

Their business depends on their search engine ranking position (SERP's) on Google. Hyperlinks connect the web and determine SERP's. Thus, the most powerful weapon RapGenius can deploy is a series of powerful hyperlinks. You can see in Mahbod's email that he is asking for hyperlinks from high-page rank sites (personal blogs) with anchor text that mentions tracks from Bieber's most recent album.

Furthermore, the 80-20 rule applied to RapGenius's business indicates that 80% of their traffic comes from only a select 20% of their lyrics database. According to Alexa.com, "Get Lucky" and "Holy Grail" were the top traffic drivers to RapGenius for most of 2013. However, music is highly cyclical, and the traffic from previous winners will eventually fade. Looking forward into 2014, it's only logical that RapGenius would hope for Bieber's new songs to refer them enormous traffic.

Marbach said he was surprised that Rap Genius, which raised $15 million from Andreessen Horowitz, would "openly execute such a frugal strategy for their link-building efforts." I dunno about "open," emails from Rap Genius cofounders have been getting leaked left and right. On Twitter, other words were used to describe the company's strategy.

This is not the first time that Rap Genius has been accused of resurrecting things from the mid-aughts to their own advantage.

Update: The Rap Genius cofounders apologized for the tactics in an open letter to Google.

tl;dr: We effed up, other lyrics sites are almost definitely doing worse stuff, and we'll stop. We'd love for Google to take a closer look at the whole lyrics search landscape and see whether it can make changes that would improve lyric search results.

To contact the author of this post, please email nitasha@gawker.com.

[Image via Getty, email screenshot via jmarbach.com]