$BABA $AAOI $SNDK US pre-market: most popular stocks fall

Alibaba drops more than 4%, plans to issue a new share placement worth HK$80 billion;

PDD drops nearly 2%, and will release its latest quarterly results before the bell today.

Stocks related to optical communications and memory decline before the bell; AAOI falls nearly 13%,

SanDisk drops more than 5%, Lumentum drops more than 4%, SK hynix and Micron Technology both fall nearly 4%.