Here are the results of your search through the public section of the IEEE Standards MA-L database report for 30-01-00:
A4-B1-21 (hex) Arantia 2010 S.L. A4B121 (base 16) Arantia 2010 S.L. Volta do Castro s/n Santiago de Compostela A Coruña 15706 ES
00-14-89 (hex) B15402100 - JANDEI, S.L. 001489 (base 16) B15402100 - JANDEI, S.L. POL. IND. POCOMACO, E-28 LA Coruña 15190 ES
00-11-B2 (hex) 2001 Technology Inc. 0011B2 (base 16) 2001 Technology Inc. 7F-10, 79 Hsin Tai 5th. Rd. Sec.1 Hsi Chih Taipei County 221 TW
00-C0-4A (hex) GROUP 2000 AG 00C04A (base 16) GROUP 2000 AG P.O. BOX 331 CH
58-84-E4 (hex) IP500 Alliance e.V. 5884E4 (base 16) IP500 Alliance e.V. Scharnhorststraße 16 Berlin 10115 DE
C4-93-13 (hex) 100fio networks technology llc C49313 (base 16) 100fio networks technology llc 2534 crescent st. apt 3F Astoria New york 11102 US
00-09-7F (hex) Vsecure 2000 LTD. 00097F (base 16) Vsecure 2000 LTD. 11 Moshe Levi St. Rishon LeZion 75658 IL
C4-01-CE (hex) PRESITION (2000) CO., LTD. C401CE (base 16) PRESITION (2000) CO., LTD. 42/6 Moo6 Muang Samutsakorn 74000 TH
70-02-58 (hex) 01DB-METRAVIB 700258 (base 16) 01DB-METRAVIB 200 CHEMIN DES ORMEAUX LIMONEST CEDEX RHONE 69578 FR
00-08-1A (hex) Sanrad Intelligence Storage Communications (2000) Ltd. 00081A (base 16) Sanrad Intelligence Storage Communications (2000) Ltd. 32 Habarzel St., Entrace B IL
Your attention is called to the fact that the firms and numbers listed may not always be obvious in product implementation. Some manufacturers subcontract component manufacture and others include registered firms' MA-L in their products.