Rivian Automotive is a company that makes electric cars and trucks. Some people who have lots of money think the company will do well in the future, so they bought options to own more shares later at a lower price. This means they are bullish or optimistic about the company. Other people think the company might not do well, so they sold some options and collected money from them. This means they are bearish or pessimistic about the company. The article is telling us that there was a lot of unusual activity with these options, which could mean something big is going to happen with the company soon. Read from source...

- The title is misleading and sensationalized. It implies that the whales are doing something specific or unusual with RIVN, but does not provide any evidence or details to support this claim. A more accurate title would be "Some Large Investors Show Interest in Rivian Options" or "Uncommon Options Trades Detected for Rivian".
- The article relies on vague and subjective terms like "bullish" and "bearish" to describe the sentiment of the whales, without providing any context or criteria for these labels. How are these sentiments measured? What factors influence them? How do they compare to previous trends or expectations? The article should provide more clarity and analysis on this topic.
- The article uses unsupported assumptions and speculation to imply causality and prediction. For example, the sentence "when something this big happens with RIVN, it often means somebody knows something is about to happen" suggests that the whales' actions are indicative of some insider information or upcoming event, but does not provide any evidence or source for this claim. The article should be more cautious and transparent about its claims and sources.

Bullish
Reasoning: The article mentions that investors with a lot of money have taken a bullish stance on Rivian Automotive, as evidenced by the options trades showing up on publicly available history. Additionally, 60% of these big-money traders are bullish and only 40% bearish. Therefore, the sentiment of the article is bullish.