Experimental (i.e., unreleased) strains are identified by a number with a state or province code letter prefix. Additional code letters may be used to designate the individuals within a state or province that developed the strain. These codes are a compilation of codes used in the Northern and Southern Uniform Soybean Tests since 1943.

^{A.E.S = Agricultural Experiment Station}

A	Iowa A.E.S. (A=W. Fehr, AR=S. Cianzio, AX, AP, AD=D.E. Green)
Ar	Arizona A.E.S.
AS	Alabama A&M Univ.
Au	Alabama A.E.S.
B	Southwestern Irrigation Field Station, Brawley, CA and US Regional Soybean Lab., Urbana, IL
C	Purdue (Indiana) A.R.P. (C=J.R. Wilcox, CL=A. LeRoy, CX, CR=K. Rainey)
CM	Canada Dept. of Agriculture, Morden, Manitoba
Co	Coker Pedigreed Seed Co., Hartsville, SC
D	Mississippi A.E.S.
D; DA; DB; DT; DS; DMK; LG	Delta Branch Experiment Station and USDA-ARS at Stoneville, MS
DSN	Indiana NAM Strains (K. Rainey, B. Diers, J. Specht)
E	Michigan A.E.S.
F	Florida A.E.S.
FWH	Florida A.E.S. Walnut Hill, FL
FC	Forage and Range Research Branch, USDA
Ga; G	Georgia A.E.S.
Note: A "T" in a Georgia number indicates selection made at Tiffton
H	Ohio A.R.D.C. (HC=R.L. Cooper, HF=R. Fioritto, HS=S.K. St. Martin/L. McHale, HM=L. McHale, HX, HC=R.L. Cooper, HW=A.K. Walker)
J	Delta Branch A.E.S., West Tennessee A.E.S and ARS
J.E.W.	John Wannamaker, St. Matthews, SC
JTN	Tennessee A.E.S., Jackson, TN and USDA-ARS
K	Kansas A.E.S.
Ky	Kentucky A.E.S.
L	Illinois A.E.S. (LD=B. Diers, LG=R.L. Nelson, LN=C.D. Nickell, LS=M. Schmidt, LA LD LU=R.L. Cooper, LN=C.D. Nickell)
Note: Second "L" in a number indicates selection made at Eldorado, IL
La	Louisiana A.E.S.
LS	Southern Illinois University (LS= L. Schmidt)
M; II	Minnesota A.E.S.
Md	Maryland A.E.S.
Me	Maine A.E.S.
N; C; NCC; NTC; NTCPR; TCWN; JWB; NLM	North Carolina A. E. S. and USDA-ARS
ND	North Dakota A.E.S.
NDPJE	North Carolina A. E. S. and USDA-ARS
O, OT, B	Central Experiment Farm, Ottawa, Ontario
O, OX	Research Station, Harrow, Ontario
OAC	University of Guelph, Guelph, Ontario
OK	Oklahoma Agricultural Experiment Station
ORC	Ridgetown, Ontario
OT	Central Experimental Farm, Ottawa, Ontario
OX	Research Station, Harrow, Ontario
P	Paymaster Farm, Plainview, TX
PI	Plant Inventory
R	Arkansas A.E.S.
Rebel	Stoneville Pedigreed Seed Co., Stoneville, MS
RJ	Arkansas State University, Jonesboro
S; LG	Missouri A.E.S. (SS=D.Sleper UM Delta Center, SA=A. Scaboo)
SA	Missouri A.E.S. (SS=D.Sleper or UM Delta Center)
SC	South Carolina A.E.S. Clemson, SC
SD	South Dakota A.E.S.
SL	US Regional Soybean Laboratories - Illinois and Missouri
TN	Tennessee A.E.S.
Ts	Texas A.E.S.
TSB	Texas A.E.S, Beaumont, TX
T	Soybean Genetic Type Collection, USDA, Urbana, IL
UA	Arkansas A.E.S., Univ. of Arkansas
U, NEX	Nebraska A.E.S.
UD	Delaware A.E.S.
UM	University of Manitoba, Winnipeg, Manitoba
UT	Tennessee A.E.S.
V; B	Virginia A.E.S., Virginia Tech
VS	Virginia A.E.S., Virginia State University
W	Wisconsin A.E.S.