In 2010, Foursquare cofounder Naveen Selvadurai believed that his company, and several other social-media upstarts—Twitter, Tumblr, Path—could carve out successful niches against Facebook.

But Facebook had other plans. That year the company introduced a feature that allowed users to “check in” at any location, a copy of the main feature of Foursquare’s app. In response, Selvadurai conceived an “anti-Facebook alliance” of up-and-coming social-media Davids taking on their industry’s Goliath. At a minimum, they could share survival tactics. Selvadurai had informal discussions with friends at Path, Instagram and Twitter, all of which had faced threats of Facebook copying key features. “It was common knowledge, even back then, that Facebook would just approach a company and say something to the effect of, ‘Join us or we will copy you,’ ” he says. More broadly, they believed that Facebook’s closed-off “walled garden,” was hurting the thing they loved most about the open Internet—the fact that anyone could build something that could reach millions of people.

The alliance didn’t get very far. In 2012, Facebook snapped up Instagram for $1 billion. The next year Yahoo acquired Tumblr for $1.1 billion. Path declined in popularity and eventually sold. Foursquare remains independent, but had to split its app into two products and adopt a new strategy.

Selvadurai, who left Foursquare in 2012, cites many reasons for the company’s struggles, from arriving before users were comfortable sharing their locations online to Facebook’s mimickry. “It’s really fun to work” on consumer Internet products, he says. “But why is it getting harder and harder over the years? Because these big players are getting bigger and bigger.”

Now, Facebook is facing challenges on many fronts. Congress is investigating how Russia used Facebook to influence the 2016 election. Privacy activists criticize Facebook’s cooperation with censorious governments. Some regulators believe the company has become too large and powerful. The media industry is wary of its control over distributing content. And, in its own backyard, many in Silicon Valley believe Facebook’s aggressive competitive strategy is stifling innovation.

Since 2012, Facebook has repeatedly copied or acquired social-media apps that gain traction. There’s the Instagram deal, and more astonishingly, its $22 billion acquisition of WhatsApp. Facebook attempted to acquire Snap for $3 billion, was turned down, and made at least 10 attempts to copy its most distinctive features. Last week the company acquired tbh, an anonymous app for teens that has bubbled up in recent months.

Facebook likely found out about tbh through one of its other acquisitions. In 2013, Facebook bought Onavo, an Israeli startup that makes an app that lets people monitor how much mobile data they’re using. After Facebook bought Onavo, it used the aggregated data from its millions of users to track which apps are growing in popularity, the Wall Street Journal reported in August. Onavo data reportedly convinced Facebook it should pursue WhatsApp and copy live video streaming services Periscope and Meerkat.

Facebook isn’t the only Silicon Valley company that competes aggressively against upstarts. Amazon started a price war with Diapers.com, then bought the weakened rival. When Google Maps competitor Waze became popular, the company bought it. But the speed at which Facebook identifies its targets, the amount of money it is willing to pay, and the shamelessness of its copycat products goes beyond its peers.

Many observers believe Facebook is bucking Silicon Valley convention, where competition is expected, but “innovation” is sacred. Tech companies have always understood that they might be overtaken by upstart disrupters. They all started as upstart disrupters, and everyone’s read Only the Paranoid Survive and The Innovator’s Dilemma. Startups are the lifeblood of Silicon Valley, and it’s an insular industry that often operates like a small town. No one wants to be seen as a bully, choking off a young startup’s chance at success.