News about Apple ordering DRAM chips sent Samsung’s stock price tumbling today, erasing a staggering $10 billion of the electronics giant’s market cap. The report stated that Apple had placed a large order for the chips from Elpida, a Samsung rival that has been enduring financial struggles.

According to Reuters, Samsung’s stock price dropped by just over 6% to $1,100 per share. That was the stock’s lowest price in nine weeks, and the worst single-day fall in four years.

Surprisingly, the news that appears to have precipitated the crash comes from DigiTimes. DigiTimes reported yesterday that Apple had placed an order with Elpida for approximately 50% of the total DRAM chip output from the company’s Hiroshima, Japan plant. What makes this interesting is DigiTimes’s reputation. The publication has a somewhat spotty record for accuracy, to put it delicately, especially when it comes to Apple-related rumors.

If the fact that Apple’s purchasing habits could cause Samsung’s stock to crash seems odd to you, it may help to bear in mind Samsung is a major supplier of components for Apple products. Despite the two companies’ ongoing competition (and legal battles) in the smartphone market, Apple remains one of Samsung’s largest component customers. If Apple really is looking to start purchasing DRAM from one of Samsung’s competitors, it could have significant implications for Samsung.