Rivian Stock Rallies as Robotaxi Buzz Builds

Key Points

• Rivian stock could be next in line after Uber's partnership announcement with Lucid, a new robotaxi wave could send it to new highs.
• Short interest is high enough to trigger a short squeeze, and that is a bet institutional buyers are making.
• With a potential scenario, Lyft could choose Rivian as a partner in this new robotaxi boom.

A new hype cycle is currently underway in the world of electric vehicles (EVs). This time, it isn’t due to a technological breakthrough or a macro backdrop fueling more and more of the risky and new companies now emerging in the entire stock market. This time, it seems EVs are booming due to a new untapped market that just entered the scene.

Shares of Rivian Automotive Inc. NASDAQ: RIVN have jumped by as much as 19.6% over the past quarter alone, a move that followed the stock's tight channel over the past year, with a 12-month performance as low as a 19.3% loss for most of that period.

That new jump and bullish renewal came from a wave that is getting started today.

Uber Technologies Inc. NYSE: UBER announced a new partnership with EV company Lucid Group Inc. NASDAQ: LCID to operate a new robotaxi fleet and service, in addition to the traditional ride-sharing services that have propelled the company to its current success.

With other companies in both the EV and robotaxi sectors quietly growing without media and hype exposure, it makes sense for Rivian to be one of the potential players that explodes in an unexpected announcement, like Uber’s.

Markets Are Betting on Something Big in Rivian Stock

Considering that Uber has now become the pioneer of partnering a ridesharing service with autonomous driving capabilities along with EVs, it shouldn’t come as a surprise for investors to see other competitors start to hop on this new wave before they get left behind in the future of the automotive sector.

One up-and-coming name that is synonymous with Uber is Lyft Inc. NASDAQ: LYFT. As far as everyone knows, Lyft hasn’t approached any EV company to partner on this robotaxi capability. That leaves Rivian open for the taking as the next of kin to Lucid’s vehicles in the market.

While this is a fairly speculative scenario with zero traction other than the Uber decision, investors have very little downside risk in being exposed to this $16.9 billion company. This makes Rivian a low-risk, high-reward investment opportunity, especially if the scenario of Lyft announcing the next potential partnership materializes.

With this in mind, and considering the recently bullish momentum in the stock, there is one major factor that investors need to consider moving forward: where the massive upside potential in Rivian stock could be realized in the coming months or even sooner.

Rivian’s Short Interest: Ticking Time Bomb

Whenever too much of a stock’s float is held in short positions, that stock’s short interest will rise to a level that is considered dangerous. This is dangerous for the bears because if a stock like Rivian were to rally by double digits (as it has) in a single week, many of these short positions could be forced to be closed.

Closing a short position involves buying back the stock that was sold short to cut the loss or take a profit; this creates additional buying pressure for the underlying stock, which is precisely why Rivian is placing short sellers at risk and facing a massive potential rally.

Looking into Rivian’s short interest today, this is where investors can take a view on a potential short squeeze, which occurs when a large number of short positions are forced to close in bulk. Considering that up to $2.1 billion worth of short positions are held in Rivian stock, or 21.3% of the entire float, it is likely that significant buying pressure could emerge.

And not only from the short sellers' side of the equation, buying pressure could also come from institutional buyers who hunt for upside momentum plays like Rivian in this current setup, meaning that the risk-to-reward ratio here greatly favors the buyers, a factor that investors should not ignore in their development for a potential buy thesis.

In fact, some recent buyers as of late July 2025 were triggered by this recent momentum in Rivian stock. Institutional buyers from ASR Vermogensbeheer decided to boost their holdings in Rivian stock by as much as 10.7% during this period, bringing their net position to a high of $2 million today.

All told, investors should watch out for what the Lyft stock price does in relation to Uber’s since any unusual lockstep or movement could indicate that something is brewing in the background, with a high probability that the catalyst is a new announcement to partner with Rivian for robotaxi offerings.