Here are the key things to know about Uber's ties to the self-driving startup accused of stealing Google's technology

Google's self-driving-car company Waymo filed an explosive lawsuit Thursday, alleging that Uber has used intellectual property stolen from Google in order to jump start its self-driving-car efforts.

The allegedly stolen technology revolves around the "lidar" sensor - a key component of self-driving cars that uses lasers to map the surrounding environment. Here's what we know so far:

• Waymo learned of the alleged theft after one of its employees was inadvertently copied on an email that included machine drawings of what appeared to be Uber's lidar circuit board. Waymo claims the drawings bore a "striking resemblance" to its own lidar system.
• At the center of the lawsuit is Anthony Levandowski, an original team member of Google's self-driving-car project who left the company to co-found Otto, a self-driving-truck startup Uber acquired.
• The suit claims Levandowski downloaded 14,000 highly confidential files and trade secrets, including Waymo's lidar circuit board design.

So, the three big questions that need to be answered are:

1. Was Waymo's technology really stolen by the founders of Otto?
2. If it was, did Uber knowingly acquire Otto to get the technology?
3. Or did Uber simply perform inadequate vetting when it acquired Otto?

It may be awhile before we learn the answers. But in the meantime, here's everything you need to know about Uber's relationship with Otto:

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