Good morning kim,
This seems to be a specific instance of "covenants". I believe, that there are
vague plans to possibly include OP_CHECKSIGFROMSTACK, which would allow
covenants much more generally, but with more complex (clever) SCRIPT.
The specification of the behavior of the opcode is
Discussing the possibility of a new opcode (OP_CHECKTXOUTSCRIPTHASHVERIFY)
for the Bitcoin scripting system that allows a transaction output to be
only spendable in a predefined manner.
*Brief Description*
Bitcoin transactions have a txoutScript (scriptPubKey) field for each
output.
