Jay Grdina at the XBiz Awards, November 17, 2005
|Born||John G "Jay" Grdina
October 11, 1967
John G. "Jay" Grdina (born October 11, 1967) is an American businessman and pornographic actor. His family originates from Croatia. He is often credited under the stage name Justin Sterling.
Grdina was born in Ohio to a wealthy cattle ranching family who immigrated from Karlovac, Croatia. He spent portions of his grade school years at Naples Christian Academy (NCH) in Naples, FL and his high school years at Gilmour Academy, a prep school in Gates Mills, Ohio. He attended  the University of San Diego majoring in business and psychology.
After school, Grdina pursued a variety of careers and business ventures until 1992, when he began investing in adult films directed by Michael Ninn. From 1995 to 1999, he wrote and directed several pornographic films in Ninn's style, often under the name 'Michael Santangelo, Justin Fine and Justin Sterling.
Grdina met Jenna Jameson, already a famous porn star, in 1998. They married in a Roman Catholic-style ceremony on June 22, 2003. The couple resided in Scottsdale, Arizona in a 6,700-square-foot (620 m2) Spanish-style mansion purchased for $2 million in 2002. They later moved to Paradise Valley in a 10,000 sq ft (930 m2) home for $4.5 million.
In 2000, founded Club Jenna Inc, first as an Internet pornography company then Grdina expanded it into a multimedia adult entertainment business bringing in an estimated $30 million per year. Featuring everything from fresh content starring Jenna to advice columns and links to plastic surgery centers, ClubJenna.com began a meteoric rise during the dot-com explosion. The site was profitable within three weeks. Club Jenna was run as a family business with Grdina's sister Kris as Vice President in charge of merchandising. Jenna marketed the company into mainstream press, driving traffic, revenues, and notoriety to the brands. On June 22, 2006, Playboy Enterprises announced the acquisition of Club Jenna and related companies in conjunction with personal service agreements by both Jameson and Grdina.
Grdina produced, directed, and wrote Club Jenna films including Briana Loves Jenna, The Masseuse, I Dream of Jenna, and Krystal Method. Grdina also acted in some of these films, as the only man that Jameson would have intercourse with on screen.
- 2005 AVN Award: "Best Actor - Film" (The Masseuse)
- 2005 AVN Award: "Best Couple Sex Scene - Film" (The Masseuse with Jenna Jameson).
- 2005 AVN Award: "Best Editing - Video" (Bella Loves Jenna)
- 2006 AVN Award: "Best Editing - Video" (Provocateur)
- 2007 AVN Award: "Best Actor" (Janine Loves Jenna)
- "Club Jenna, Inc." Hoover's coverage by Joe Bramhall
- Dnevno.hr Ratko Martinović: Loš PR u dijaspori - Koje su svjetski poznate osobe podrijetlom Hrvati, a da to niste ni znali, 28. listopada 2012. (Croatian)
- "The (Porn) Player", by Matthew Miller, Forbes magazine, July 4, 2005
- Brand Access Forum May 8, 2006 Los Angeles, California speaker profile. Archived from  on 2006-05-08 by the Internet Archive
- "Club Jenna’s Playboy: Jay Grdina on Relationships, Religion and Celebrity Sex Tapes", Sex Herald, Volume 4-Issue 9, 2007. Retrieved 2007-06-27.
- Justin Sterling at the Internet Movie Database
- "Justin Sterling" page about the director at lukeford.com
- "At Home with Jenna Jameson: Off Camera, Cashmere and Crosses" by Dinitia Smith, The New York Times, April 15, 2004
- "Playboy gets more hardcore with new acquisition", by William Spain, MarketWatch, June 22, 2006
- "Jenna Jameson files for divorce", United Press International, December 12, 2006