Here's what we can tell you: The Cleveland Browns are searching for candidates to replace offensive coordinator Kyle Shanahan.
What we can't say is who specifically has set foot in the building.
The following is a list of names linked by media reports to the opening.
Resume: Steelers OC (1996-97), Dallas Cowboys HC (98-99), Miami Dolphins OC (2000-01), Georgia Tech HC (02-07), Kansas City Chiefs OC (2008), Buffalo Bills HC (2010-2012)
Style of offense: Spread passing. Read a breakdown of it here.
Claim to fame: Made the playoffs in back-to-back seasons with the Cowboys before he was abruptly fired.
Fun fact: Played quarterback at the University of Florida (1971-1973).
Resume: Oakland Raiders QB assistant (2007-08), New York Jets* QB coach (2009), San Jose State QB coach (2010-11), Oakland Raiders QB coach (2012-present)
Style of offense: Has never called plays before, but also interviewed for the Browns coordinator job last season.
Claim to fame: Tutored rookie quarterback Derek Carr, who threw for 3,270 yards, 21 touchdowns and 12 interceptions in 2014.
Fun facts: He's a Youngstown native who played quarterback at James Madison (1996-1999). DeFilippo's dad, Gene, was the athletic director at Boston College (1997-2012).
*Indicates he was on the same coaching staff as Mike Pettine
Resume: Baltimore Ravens* OC (1999-2004), University of Pittsburgh OC/QB coach (2005-08), New York Jets* QB coach (2009-2012), Chicago Bears QB coach (2013-14)
Style of offense: Conservative West Coast with heavy emphasis on the run. Last called plays at the NFL level in 2004.
Claim to fame: Behind All-Pro running back Jamal Lewis, he helped guide the Ravens offense to a Super Bowl title in 2001.
Fun facts: Began his coaching career alongside Pettine in 1993 at Pitt and later got Pettine the video internship with the Ravens that launched Pettine's career. He also was a longtime backup quarterback in the NFL, winning Super Bowls with the San Francisco 49ers and New York Giants.
Resume: Philadelphia Eagles OL coach (1995-97), Oakland Raiders OC (1998-2001), Oakland Raiders HC (2002-03), Nebraska HC (2004-2007), New York Jets AHC/OL coach (2008-2011), Dallas Cowboys OC/OL coach (2012-present)
Style of offense: Tailors offense to the talent he has using west coast and zone blocking concepts. Raiders led the NFL in rushing in 2000 under Callahan and then led the league in passing in 2002. He's widely known as an offensive line guru.
Claim to fame: As a rookie head coach, he led the Raiders to Super Bowl XXXVII.
Fun facts: Played quarterback in college at Benedictine University in Illinois.
Resume: Louisville OC/QB coach (1998-2001), Minnesota Vikings OC/WR coach (2002-2004), Miami Dolphins OC (2005), St. Louis Rams HC (2006-2008), Detroit Lions OC (2009-2013), Dallas Cowboys passing game coordinator (2014-present)
Claim to fame: The 2003 Vikings led the league in total offense while Randy Moss boasted 17 touchdown receptions. Linehan called plays for what arguably turned out to be Tony Romo's and DeMarco Murray's best career seasons in 2014.
Style of offense: Known as a quarterback-friendly system that "takes what the defense gives us," Linehan described when he was first hired in Dallas.
Fun facts: Quarterback at the University of Idaho (1982-1986), signed as a rookie free agent with the Dallas Cowboys in 1987 but suffered a career-ending shoulder injury.
Resume: New York Jets OC (1997-99), New England Patriots OC (2000-04), Notre Dame HC (2005-09), Kansas City Chiefs OC (2010), University of Florida OC (2011), University of Kansas HC (2012-2014)
Claim to fame: Calling plays for two Patriots Super Bowl champion teams and helping mold Tom Brady as a young quarterback.
Style of offense: Creativity. Read about his use of the unbalanced offensive line that he implemented with the Chiefs. And Weis recently came out and said he's a big fan of having an athletic quarterback with the ability to scramble.
Fun facts: Has heavy ties to both Bill Parcells and Bill Belichick. Created the Hannah & Friends Foundation dedicated to improving the quality of life for children and adults with special needs. Weis also coached high school football in New Jersey for five years to start off his career, similar to Pettine.
Resume: Kansas City AHC/WR coach (1989-1998), St Louis Rams AHC/WR coach (1999-2000), Kansas City Chiefs OC (2001-05), Washington Redskins AHC (2006-07), St. Louis Rams OC (2008), Baltimore Ravens offensive consultant (2009-2010), Oakland Raiders OC (2011), Oakland Raiders senior offensive assistant (2012-present).
Claim to fame: The Chiefs averaged an NFL best 380.9 yards per game in 2001-05 while Saunders called the plays.
Style of offense: Known as a passing game guru who will challenge players to study hard. Saunders reportedly had a 700 page playbook with up to 1,800 play calls when he was coordinating the Redskins offense.
Fun facts: He was born in England and was an Academic-All American wide receiver and defensive back at San Jose State. Saunders enjoys distance running.
Resume: Oakland Raiders QB coach (2001), Oakland Raiders OC (2002-03), Miami Dolphins AHC (2004), North Carolina State OC (2005-06), Montreal Alouettes HC (2008-2012), Chicago Bears HC (2013-14)
Claim to fame: Won two Grey Cups in the CFL with Montreal.
Style of offense: Wide-open and aggressive with lots of shotgun formations.
Fun facts: Trestman was actually the Browns quarterbacks coach and offensive coordinator in 1988-89 and worked closely with Bernie Kosar. Trestman wrote a book in 2010 called *PERSEVERANCE: Life Lessons on Leadership and Teamwork. *
Resume: Denver Broncos special teams assistant (2000-02), Jacksonville Jaguars RB coach (2003-04), Dallas Cowboys RB coach (2005-06), Cleveland Browns RB coach (2007-08), New York Jets* RB coach (2009-2011), New York Jets AHC/RB coach (2012-present)
Claim to fame: Helped guide the Jets to a franchise-record 2,756 rushing yards behind Thomas Jones and Shonn Greene.
Style of offense: Has never called plays at the NFL level.
Fun facts: Won three Super Bowls as a player – one with the 49ers and two with the Broncos.