Microsoft’s stock rose 0.7% Friday, giving it a market cap of $851 billion, according to Nasdaq. Apple’s stock, which fell 1%, closed the day worth $847 billion. Microsoft briefly surpassed Apple in market cap earlier this week. The last time its stock was the most valuable in the U.S. was in 2002. Others such as GE, Exxon Mobile, and Apple have held that title since then.

For the past several years, Apple has ruled as the U.S. stock with the largest market cap. In August, Apple’s market cap even rose above the $1 trillion level, becoming the first U.S. stock to achieve that worth. Amazon shortly followed with a $1 trillion market value, but both stocks have since tumbled after indicating that their revenue this quarter could disappoint.

Microsoft, meanwhile, held up relatively well during the selloff in tech stocks in the past month. One reason is Microsoft’s early embrace of the enterprise-cloud market. Microsoft entered the cloud services market in 2011 and has a 13% share of it, according to Synergy Research. It’s second only to Amazon, which launched Web Services a few years earlier, and holds a 33% share of that market.

Satya Nadella, Microsoft’s CEO since 2014, has made enterprise-cloud services like Azure a priority. Under his predecessor Steve Ballmer, Microsoft began to move away from its reliance on Windows PC operating software, pushing into enterprise software.

Microsoft and Apple were bitter rivals for decades. The two companies emerged as leaders in the 1980s during the early days of the personal computer industry. Microsoft became a juggernaut among software makers, while Apple and other Silicon Valley companies fought for market share. Microsoft’s dominance in the PC software market gave it a market value that was larger than Apple’s for years.

In early 2010, Apple’s market cap surpassed that of Microsoft and remained above it for the next eight years, as consumers moved away from desktop computers in favor of smartphones and tablets. Apple introduced the iPhone in 2007 and the iPad in 2010. Since then, Microsoft has opened up to other software platforms, with the bitterness of the past rivalry having faded into history.