Ivan Panfilov (b. 1870) is recorded as working in St. Petersburg between 1902-1917, and working for Fabergé.
(T. Fabergé, A. Gornia, V. Skurlov, Fabergé and Petersburg Jewellers, St. Petersburg, 1997, p. 132.)
The Cyrillic initials IP are also recorded as found in combination with Fabergé's mark (G. von Habsburg, Fabergé, London, 1988, p. 332).