MetaTrader5 Python 5.0.6231 / terminal build 6249: tick flags 0x80

For MetaTrader5 Python package 5.0.6231 with MetaTrader 5 terminal build 6249, what is the official meaning of bit 0x80 (128) in the flags field returned by copy_ticks_range()?

May downstream software ignore this bit while interpreting the documented tick flags, or does it require special handling?

Please provide a MetaQuotes specification or a version-applicable technical reference.