I only took a quick look, but it's very likely some LZSS variant. Why?
$80/9BDA C2 30 REP #$30
$80/9BDC A7 10 LDA [$10] ; read first flag bits
$80/9BDE E6 10 INC $10
$80/9BE0 E6 10 INC $10
$80/9BE2 85 0A STA $0A
$80/9BE4 A0 10 00 LDY #$0010 ; initially 16 flag bits left (the two bytes just read)
$80/9BE7 46 0A LSR $0A ; get next flag bit
$80/9BE9 88 DEY
$80/9BEA D0 0B BNE $0B [$9BF7] ; need to read new flag bits?
(read new flag bits if necessary)
$80/9BF7 90 0E BCC $0E [$9C07] ; was flag bit cleared or set?
(branches back to $9BE7)
It loads two bytes (16 bits) into $0a and each iteration checks whether the LSB was set or not. If it runs out of flag bits (all 16 bits were checked), it reads the next two bytes. How it reacts on each flag bit being set or not depends on the concrete algorithm.
This pattern almost always indicates an LZSS variant.