▁created ▁by ▁a ▁split ▁from ▁ 7 1 4 ▁on ▁November ▁ 5 , ▁ 1 9 8 2 ; ▁split ▁off ▁ 7 6 0 ▁on ▁March ▁ 2 2 , ▁ 1 9 9 7 ▁and ▁ 8 5 8 ▁on ▁June ▁ 1 2 , ▁ 1 9 9 9 ; ▁re - mer ged ▁with ▁ 8 5 8 ▁in ▁June ▁ 2 0 1 8 ▁to ▁create ▁the ▁ 6 1 9 / 8 5 8 ▁overlay ▁ 6 2 6 ▁– ▁Pas ad ena , ▁El ▁Monte , ▁West ▁Cov ina ; ▁the ▁San ▁Gabriel ▁Valley ▁and ▁eastern ▁sub ur bs ▁of ▁Los ▁Angeles . ▁( Split ▁from ▁ 8 1 8 ▁on ▁June ▁ 1 4 , ▁ 1 9 9 7 ) ▁ 6 2 8 ▁– ▁Over lay ▁with ▁ 4 1 5 ▁effective ▁March ▁ 2 1 , ▁ 2 0 1 5 ▁ 6 5 0 ▁– ▁San ▁Mate o , ▁Pal o ▁Al to , ▁Red wood ▁City , ▁Dal y ▁City ; ▁most ▁of ▁San ▁Mate o ▁County ▁and ▁north western ▁Santa ▁Clara ▁County ▁( i . e ., ▁the ▁San ▁Francisco ▁Pen ins ula ▁with ▁the ▁exception ▁of ▁the ▁city ▁and ▁county ▁of ▁San ▁Francisco ). ▁( Split ▁from ▁ 4 1 5 ▁on ▁August ▁ 2 , ▁ 1 9 9 7 ) ▁ 6 5 7 ▁– ▁Over lay ▁with ▁ 7 1 4 ▁on ▁September ▁ 2 3 , ▁ 2 0 0 8 ▁ 6