I confirm that filter in is cleartool findnot possible:
ct find . -ele "lbtype_sub(My_LAB*)" -print
will not work (no wildcard in the query argument .
If you cannot use grep in a shell connection, can you use grep in the exec part found, as in this example ?
ct find . -kind lbtype -exec "echo %CLEARCASE_PN%|grep MY_LAB"
If this is unacceptable, you need to write the result to a file and process it with another tool (sed?)
Windows, Unix: . SO.
grep.
Windows, FIND ( ).