There is one mark on back, It does look like it's from when it was made. And from what I can see there are only a couple small tiny bubbles.
Please take a look at each photo and if you have any questions just ask. The item "Fenton Carnival Glass Captive Rose Cobalt Blue 9 1/4 Plate" is in sale since Tuesday, August 28, 2018.This item is in the category "Pottery & Glass\Glass\Glassware\Carnival Glass\Vintage (Pre-1940)\Fenton". The seller is "apri_llewe" and is located in Daytona Beach, Florida. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Philippines, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Colombia, Costa rica, Dominican republic, Panama, Trinidad and tobago, Guatemala, El salvador, Honduras, Jamaica, Antigua and barbuda, Aruba, Belize, Dominica, Grenada, Saint kitts and nevis, Saint lucia, Montserrat, Turks and caicos islands, Barbados, Bangladesh, Bermuda, Brunei darussalam, Bolivia, Ecuador, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Cayman islands, Liechtenstein, Sri lanka, Luxembourg, Monaco, Macao, Martinique, Maldives, Nicaragua, Oman, Peru, Pakistan, Paraguay, Reunion, Viet nam, Uruguay, Russian federation.