What is the best company to obtain a certificate of authenticity from autograph sports?

I am looking to buy a soccer ball dedicated to a friend for the holidays and do not know the difference of a COA from another – the last time I looked a certificate of authenticity Global Authentication Inc. (GAI) and is playing with a stick supporting evidence and the serial number. Is this a good company and if not what company should be looking for when it comes autographs? Thanks

now that you mentioned is as good as you get it, is trustworthy and worth buying

O Día do Orgullo Gai con máis actos ca nunca

Jon Lester Signed Rawlings OMLB Red Sox GAI COA $69.99

Mike Mussina Signed Rawlings OLB NY Yankees GAI COA $59.99

Don Drysdale Autograph Signed 3×5 Postcard COA GAI $65.00

Don Drysdale Autograph Signed 3×5 Postcard COA GAI $75.00

Jordan Farmar Signed Auto UCLA Bruins Jersey GAI COA $125.10

Robin Roberts autographed Rawlings baseball-GAI COA $14.99

Bob Feller autographed 48 World Series photo-GAI COA $6.99

SHARON STONE Autographed Signed 8×10 Photo GAI COA! $149.99

Autographed JOE DIMAGGIO and MICKEY MANTLE 8 x 10 Photo Signed with GAI Certification This is a very rare autographed photo signed by Hall of Famer’s Mickey Mantle, and Joe DiMaggio. Photo has been authenticated by GAI and has a hologram on front to prove it. This is 100% authentic. The signatures are awesome, check out the scan….

Eli manning New York Giants HAND SIGNED 8 X 10 photo COA/GAI This is a 100% AUTHENTIC HAND SIGNED AUTOGRAPHED 8 X 10 PHOTO OF THE NEW YORK GIANTS ELI MANNING AND COMES WITH A GLOBAL AUTHENTICATION INC. MATCHING COA and hologram on this NFL official licensed [photo…

Joe Dimaggio Signed Autograph 16×20 Mint!!! Gai/global Coa– Very Rare!!!! Joe Dimaggio Signed Autograph MINT 10+ —RARE!!!!!!!!!!!!!…

Joe Dimaggio Signed Autograph 16×20 Mint!!! GAI/GLOBAL COA Joe DiMaggio 16×20 signed autograph GAI/GLOBAL MINT+!!! RARE!!!!…

Main Street ( 1st/1st ~ Signed ~ GAI Certified with COA and LOA ~ The First American to Win the Nobel Prize for Literature ) …

Signed Allison, Davey / Kulwicki, Alan 8×10 By Davey Allison and Alan Kulwicki (GAI Authenticated) $875.00 Signed 8×10 By Davey Allison and Alan Kulwicki (GAI Authenticated) comes with powers collectibles coa and matching holograms…

Paul Hornung Green Bay Packer Autographed Stat Jersey w/ COA from GAI $199.00 Paul Hornung Green Bay Packer Autographed Stat Jersey w/ COA from GAI…

Autographed Ernie Banks Baseball – Selig GAI COA $150.30 MLB Memorabilia & Autographed Baseballs. Ernie Banks 500 Homerun Club Signed Baseball. GAI COA #GV83829….