Transactions listed are from November 1 of previous year to April 1 of the following year.
The Boston Beaneaters signed Harry Aubrey as an amateur free agent.
The Chicago Orphans released Sammy Strang. (Date given is approximate. Exact date is uncertain.)
The Washington Senators signed Charles Moran as an amateur free agent.
The Brooklyn Superbas signed Sammy Strang as a free agent.
The Washington Senators signed Kip Selbach as a free agent.
The St. Louis Cardinals purchased Mordecai Brown from Omaha (Western).
Doc Casey jumped from the Detroit Tigers to the Chicago Cubs.
Jack Chesbro jumped from the Pittsburgh Pirates to the New York Highlanders.
Sam Crawford jumped from the Cincinnati Reds to the Detroit Tigers.
George Davis jumped from the Chicago White Sox to the New York Giants.
Lefty Davis jumped from the Pittsburgh Pirates to the New York Highlanders.
Gene DeMontreville jumped from the Boston Beaneaters to the Washington Senators.
Cozy Dolan jumped from the Brooklyn Superbas to the Chicago White Sox.
Bill Donovan jumped from the Brooklyn Superbas to the Detroit Tigers.
Mal Eason jumped from the Boston Beaneaters to the Detroit Tigers.
Duke Farrell jumped from the Brooklyn Superbas to the Boston Americans.
Billy Gilbert jumped from the St. Louis Browns to the New York Giants.
Clark Griffith sent from the Chicago White Sox to the New York Highlanders in an unknown transaction.
Dick Harley jumped from the Detroit Tigers to the Chicago Cubs.
Jack Harper jumped from the St. Louis Browns to the Cincinnati Reds.
Willie Keeler jumped from the Brooklyn Superbas to the New York Highlanders.
Bill Keister jumped from the Washington Senators to the Philadelphia Phillies.
Jack McCarthy jumped from the Cleveland Naps to the Chicago Cubs.
Sam Mertes jumped from the Chicago White Sox to the New York Giants.
Fred Mitchell jumped from the Philadelphia Athletics to the Philadelphia Phillies.
Doc Newton jumped from the Brooklyn Superbas to Los Angeles (PCL).
Jack O'Connor jumped from the Pittsburgh Pirates to the New York Highlanders.
Alex Pearson jumped from the St. Louis Cardinals to the Cleveland Naps.
Wiley Piatt jumped from the Chicago White Sox to the Boston Beaneaters.
Tully Sparks jumped from the Boston Americans to the Philadelphia Phillies.
The Boston Americans purchased George Stone from Omaha (Western).
Jesse Tannehill jumped from the Pittsburgh Pirates to the New York Highlanders.
John Warner jumped from the Boston Americans to the New York Giants.
Doc White jumped from the Philadelphia Phillies to the Chicago White Sox.
The Pittsburgh Pirates signed Brickyard Kennedy as a free agent.
The St. Louis Cardinals traded Otto Krueger to the Pittsburgh Pirates for Jimmy Burke.
The Philadelphia Phillies selected Chief Zimmer off waivers from the Pittsburgh Pirates.
The St. Louis Browns purchased Ed Siever from the Detroit Tigers.
The Brooklyn Superbas purchased Jack Doyle from the Washington Senators.
The Washington Senators purchased Ducky Holmes from the Detroit Tigers.
The Philadelphia Phillies released Fred Jacklitsch. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Athletics purchased Ollie Pickering from the Cleveland Naps.
The Pittsburgh Pirates selected Lave Winham off waivers from the Brooklyn Superbas.
The Brooklyn Superbas purchased Henry Thielman from the Cincinnati Reds.
The Brooklyn Superbas purchased Rube Vickers from the Cincinnati Reds.
The Brooklyn Superbas signed Fred Jacklitsch as a free agent.
The New York Highlanders purchased Dave Fultz from the Philadelphia Athletics.
Buffalo (Eastern) traded Dave Brain to the St. Louis Cardinals for Fred Hartman.
The Detroit Tigers traded Kid Gleason to the New York Giants for Heinie Smith.
The Chicago White Sox purchased Nick Altrock from the Boston Americans.
The Philadelphia Phillies purchased Warren McLaughlin from the Pittsburgh Pirates.
The Chicago White Sox purchased Jack Slattery from the Cleveland Naps.
The St. Louis Cardinals traded Bob Wicker to the Chicago Cubs for Bob Rhoads.
The Philadelphia Phillies purchased Pop Williams from the Chicago Cubs.
The Boston Beaneaters released Billy Lush.
The Boston Beaneaters returned Red Long to Lawrence (Eastern) as part of a conditional deal.
The Detroit Tigers signed Billy Lush as a free agent. (Date given is approximate. Exact date is uncertain.)
The Chicago Cubs released John Dobbs. (Date given is approximate. Exact date is uncertain.)
The Brooklyn Superbas signed John Dobbs as a free agent.
Worcester (Eastern) loaned Reddy Grey to the Pittsburgh Pirates.
Ernie Diehl sent from ??? to the Pittsburgh Pirates in an unknown transaction.
The Chicago Cubs released Jack Doscher. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Phillies purchased John Titus from Concord (New England).
The Pittsburgh Pirates purchased Art Weaver from the St. Louis Cardinals.
The Chicago White Sox traded Tom Daly and Cozy Dolan to the Cincinnati Reds for George Magoon.
The New York Highlanders traded Ernie Courtney and Herman Long to the Detroit Tigers for Kid Elberfeld.
The Washington Senators traded Ducky Holmes to the Chicago White Sox for . The Chicago White Sox sent Davey Dunkle (July 20, 1903) to the Washington Senators to complete the trade.
The Chicago Cubs purchased Clarence Currie from the St. Louis Cardinals.
The Brooklyn Superbas signed Jack Doscher as a free agent.
The Philadelphia Phillies released Pop Williams.
Baltimore (Eastern) traded Jack Hayden to the Brooklyn Superbas for Hughie Hearne, Hughie Jennings, Walt McCredie and Bill Pounds.
The Washington Senators purchased Malachi Kittridge from the Boston Beaneaters.
The New York Highlanders traded Paddy Greene to the Detroit Tigers for John Deering.
The Washington Senators traded Joe Martin to the St. Louis Browns for Barry McCormick.
The Boston Beaneaters signed Pop Williams as a free agent.
The Boston Beaneaters signed Tom Needham as a free agent.
The St. Louis Browns signed Roy Evans as a free agent.
The St. Louis Browns purchased Barney Pelty from Cedar Rapids (Three-I).
The Cleveland Naps traded Gene Wright to the St. Louis Browns for Red Donahue.
Columbus (American Association) traded Terry Turner to the Cleveland Naps for Billy Clingman and Gus Dorner.
The New York Giants released Roscoe Miller.
The Philadelphia Athletics purchased Jim Fairbank from Utica (New York State).
The St. Louis Cardinals signed Harry Betts as an amateur free agent.
The Pittsburgh Pirates drafted Howie Camnitz from Vicksburg (Cotton States) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Chicago White Sox drafted Tom Dougherty from Atlanta (Southern Association) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Phillies drafted Tom Fleming from Colorado Springs (Western) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Cincinnati Reds selected Lee Fohl off waivers from the Pittsburgh Pirates.
The Cleveland Naps purchased Jack Hickey from Seattle (PCL).
The Chicago White Sox drafted Frank Huelsman from Shreveport (Southern Association) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Washington Senators drafted Beany Jacobson from Decatur (Three-I) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Pittsburgh Pirates signed Hans Lobert as an amateur free agent.
The Brooklyn Superbas drafted Harry Lumley from Seattle (PCL) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Phillies drafted Doc Marshall from Des Moines (Western) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Phillies drafted John McPherson from Milwaukee (American Association) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Cincinnati Reds drafted Peaches O'Neill from Grand Rapids (Central) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Washington Senators drafted Champ Osteen from Davenport (Three-I) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The New York Highlanders drafted Ambrose Puttmann from Helena (PCL) in the 1903 rule 5 draft.
The New York Highlanders drafted Eddie Quick from Salt Lake City (PCL) in the 1903 rule 5 draft.
The Cincinnati Reds drafted Admiral Schlei from Denver (Western) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The St. Louis Cardinals drafted Spike Shannon from St Paul (American Association) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Chicago White Sox drafted Frank Smith from Birmingham (Southern Association) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Chicago White Sox drafted Ed Walsh from Newark (Eastern) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The Brooklyn Superbas released Tom McCreery. (Date given is approximate. Exact date is uncertain.)
The Boston Beaneaters signed Tom McCreery as a free agent. (Date given is approximate. Exact date is uncertain.)
The Washington Senators signed Joe Cassidy as a free agent.
The Philadelphia Athletics traded Tad Quinn and $2,000 to Toronto (Eastern) for Lou Bruce.
Buffalo (Eastern) traded Cy Ferry and Matty McIntyre to the Detroit Tigers for Ernie Courtney, Rube Kisinger, Sport McAllister and either Yeager or Lush.
The Pittsburgh Pirates signed Roscoe Miller as a free agent.
The St. Louis Browns traded John Anderson to the New York Highlanders for Jack O'Connor.
The Boston Beaneaters drafted Phil Geier from St Paul (American Association) in the 1903 rule 5 draft.
The Chicago Cubs traded Clarence Currie, Dick Harley, Tommy Raub and $750 to Toronto (Eastern) for Buttons Briggs. (Date given is approximate. Exact date is uncertain.)
The Philadelphia Athletics signed Jim Mullin as an amateur free agent.
The Boston Beaneaters drafted Jim Delahanty from Little Rock (Southern Association) in the 1903 rule 5 draft.
The Boston Beaneaters drafted Tom Fisher from Shreveport (Southern Association) in the 1903 rule 5 draft.
The St. Louis Browns drafted Tom Jones from Baltimore (Eastern) in the 1903 rule 5 draft.
The Boston Beaneaters drafted Fred Raymer from Columbus (American Association) in the 1903 rule 5 draft.
The Brooklyn Superbas drafted Emil Batch from Holyoke (Connecticut State) in the 1903 rule 5 draft. (Date given is approximate. Exact date is uncertain.)
The New York Giants traded Charlie Babb, Jack Cronin and $6,000 to the Brooklyn Superbas for Bill Dahlen.
The St. Louis Cardinals traded Mordecai Brown and Jack O'Neill to the Chicago Cubs for Larry McLean and Jack Taylor.
The New York Highlanders traded Jesse Tannehill to the Boston Americans for Tom Hughes.
George Davis jumped from the New York Giants to the Chicago White Sox.
The New York Giants purchased Art Devlin from Newark (Eastern).
Patsy Donovan jumped from the St. Louis Cardinals to the Washington Senators.
The Cincinnati Reds purchased Miller Huggins from St Paul (American Association).
Jersey City (Eastern) purchased Bill Keister from the Philadelphia Phillies.
Des Moines (Western) purchased Hans Lobert from the Pittsburgh Pirates.
The Pittsburgh Pirates released Kaiser Wilhelm.
The New York Giants purchased Hooks Wiltse from Troy (New York State).
The Detroit Tigers traded Billy Lush to the Cleveland Naps for Ed Killian and Jesse Stovall.
The New York Highlanders purchased Champ Osteen from the Washington Senators.
Toledo (American Association) traded Red Kleinow to the New York Highlanders for Eddie Quick and Jack Zalusky.
The Brooklyn Superbas purchased Bill Bergen from the Cincinnati Reds.
The Washington Senators purchased Jake Stahl from the Boston Americans.
The Boston Beaneaters purchased Joe Stewart from St Paul (American Association).
The St. Louis Cardinals purchased Jake Beckley from the Cincinnati Reds.
The New York Highlanders purchased Deacon McGuire from the Detroit Tigers.
The Chicago White Sox traded George Magoon to Indianapolis (American Association) for . Indianapolis (American Association) sent Mike Heydon (August, 1904) to the Chicago White Sox to complete the trade.
The Brooklyn Superbas purchased Ed Poole from the Cincinnati Reds.
St Paul (American Association) purchased Harry Aubrey from the Boston Beaneaters.
Providence (Eastern) purchased Harry Aubrey from the Boston Beaneaters.
St Paul (American Association) returned Harry Aubrey to the Boston Beaneaters following previous purchase.
The Boston Beaneaters signed Kaiser Wilhelm as a free agent.
The New York Highlanders traded Harry Howell and cash to the St. Louis Browns for Jack Powell.
Columbus (American Association) purchased John Malarkey from the Boston Beaneaters.