Big Tech companies

1
To my colleagues,

Anybody has a reliable source for the birth chart of the GAFAM
Google (Alphabet)
Apple
Facebook (Meta)
Amazon
Microsoft
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X network
Tesla
Nvidia
Baidu
Alibaba
Tencent
Xiaomi (BATX)
Broadcom
Samsung
Tencent
Oracle
Adobe

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1) When a company is sold like Twitter who became X, would you keep the original chart of Twitter as the chart of X?
2) I know many companies have birth charts set for noon when they are launched on the Stock Market. But why not use the stock market opening hours at 9:30 am in NY?

Any comments or information welcome,
Ouranos
Blessings!