if the line1 address is in wrong format shouldn't API atleast consider second line of address to give best possible result

There are three problems with your example request.First, the value of the location parameter must be fully encoded to prevent the first ampersand (&) from being used as a parameter separator; the encoded form of "&" is "%26".  Second, "87" must be preceded by a highway designator, such as "hwy" or "highway".  Third, there should be a space between "San" and "Jose".  The following request will return the desired results:

http://where.yahooapis.com/geocode?location=Hwy+87+%26+Capitol+Expressway,+San+Jose,+CA,+95136&appid=yourappid

You can also use "and" instead of "&" to separate the two street names.

Eddie Babcock
Yahoo! Geo Technologies