The people who control the Twitter accounts at BMW USA and Audi are engaging in a war of words over a photo of an M4 with an explosion of sparks in the background. The pattern just happens to look like the rings in Audi's logo.
We can see where Audi is coming from because the flaming circles do evoke the company's insignia, although there are far more than the four rings in the automaker's logo. BMW didn't ignore the gentle mocking by posting a more pointed message of its own.
Audi didn't bother to respond to BMW's reply, which ended the back and forth between the automakers. However, this isn't the first time for the companies to engage in good-hearted mockery, although it generally happens on dealer billboards rather than social media. For example, a showroom in Tunisia installed a sign in front of a local Audi factory in 2018 that said, "It’s never too late to change your mind." The Four Rings responded with a sign showing "LOOOL. We do not change a brand that wins."
In 2009, there was even more visible competition between the brands. An advertising agency erected a giant billboard on Los Angeles' famous Santa Monica Boulevard that showed a new Audi A4 with the message, "Your move, BMW." Bimmer responded with a similarly sized sign on the other side of the road showing and M3 and the single word "Checkmate."
While not quite as humorous, BMW took advantage of open advertising space in China by erecting a huge billboard touting its model's efficiency on a building that just so happened to house an Audi dealer. Customers weren't able to miss the giant image of a 5 Series when walking into the showroom to potentially shop for a new A6.