A method for detecting nets physically changed and electrically affected
by a design ECO includes steps as follows. An ECO is executed on an IC
design to produce a post-ECO IC design. A first group of nets of the IC
design physically changed by the ECO is identified by comparing a pre-ECO
database with a post-ECO database. A pre-ECO design SPEF file of the IC
design is parsed with a script to identify a second group of nets in the
pre-ECO database based on the first group of nets, the second group of
nets being coupled to the first group of nets. The second group of nets
is pre-ECO electrically affected nets. Parasitics for the first group of
nets in the post-ECO database are extracted to generate a parasitic data
file for the first group of nets. The parasitic data file is parsed with
the script to identify a third group of nets in the post-ECO database
based on the first group of nets, the third group of nets being coupled
to the first group of nets. The third group of nets is post-ECO
electrically affected nets. Finally, a file listing the first group of
nets, the second group of nets and the third group of nets is generated.