When you question them about it they will deny it.The LAST thing that should convice is the signature. Look at the quality of the piece. Prominent mold seams are atypical of Rene Lalique. He incorporated his mold seams into the design of the piece making them disappear. There are several Lalique Reference books out there, Warman's Lalique Price Guide has a section on fraudulent Lalique, which has pictures of the "Small Grape Harvest" vase.  So does A Guide To Fraudulent Lalique by Alice Bley and Carol Glaze. If you do bid on a Lalique item, make sure the seller has a good return policy, and only pay by PayPal so you have some level of protection.  Also, in the book " A Guide To Fraudulent Lalique" by Alice Bley, there is a copy of a letter from Cristal Lalique stating that items made by Lalique have never been marked or molded "Made In" France. There have been a few "Starfish" bowls marked "R Lalique Made In France"  as well as a few vases with the same marking. Cristal Lalique does apply a made in France sticker to items headed for English speaking markets, but have never marked thier items this way. The Starfish bowl is highlighted on page 17 of A guide To Fraudulent Lalique  regarding the fraudulent "Made In France " molding. Recently, there have also been several  "R Lalique" glass birds on Ebay. Most of these are Desna as well. In the book "Lalique Glass" by Nicholas M. Dawes, of Antiques Roadshow fame, there is an entire section on fakes and forgeries. On page 133 there is a picture of the small grape harvest vase seen very frequently on Ebay fraudulently marked Lalique. on the following page is a picture of one of the glass birds frequently seen on Ebay being sold as Lalique.  These are almost always marked "R Lalique France" in block letters. This was done with a stencil and a small amount of hydrofluoric acid. Lalique has never used acid to mark their work. The signature was always sand-blasted onto the finished product. You will see numerous listings stating that the item has the acid mark. This is incorrect. If you look closely you will see the edges of these have a fuzzy appearance. This indicates a fraudulent signature. I have included photos from the Desna site of some of these items.