Will Sigma still honor warranty ?

I need to return a Sigma lens for calibration... it's very soft at 500mm.  I'm getting ready to pack it in the original packaging and box that I got it new from B+H but I see I didn't fill out the warranty card.  I have a copy of my original purchase invoice from B+H and it's just over a year old. Will Sigma still honor the warranty ?  I was told it's a two year warranty.  Thanks.