To write this article about Uber's autonomous vehicle strategy pivot, I need actual source documents that include:
1. Articles or press releases about the Uber ATG sale in 2020
2. Announcements of partnerships with Wayve, Chinese AV firms, and Rivian
3. Investment disclosures showing Uber's stakes in these companies
4. Any statements from Uber executives or company filings
5. Published dates for each source
Without these source documents, I cannot cite facts or provide the required sources footer per the strict anti-hallucination guidelines.
