- Others
- Multiple EFOs per issue
1981 40s Concert at the Park issue, IMPERFORATE Vertically, Pair.
1986 3p60 Philippine Normal College, 85th Anniversary, IMPERFORATE Pair.
1985 60s and 3p00 International Telecommunications Satellite Organization (INTELSTAT) 20th Anniversary issue, IMPERFORATE, Pairs.
1983 40s San Lorenzo Ruiz Beatification issue, IMPERFORATE bottom margin.
1984 60s Kilusang Kabuhayan at Kaunlaran (KKK) - National Livelihood issue, IMPERFORATE right margin.
1978 90s Town of Balayan, 4th Centennial issue, featuring the Balayan Church. Double error - Missing "90s" value and IMPERFORATE.