diff --git a/src/mame/drivers/galdrvr.c b/src/mame/drivers/galdrvr.c
index f9b28947da0..f47d26a7a71 100644
--- a/src/mame/drivers/galdrvr.c
+++ b/src/mame/drivers/galdrvr.c
@@ -5974,8 +5974,8 @@ GAME( 198?, thepitm,  thepit,   mooncrst, thepitm,  thepitm,  ROT90,  "bootleg (
 GAME( 1982, skybase,  0,        mooncrst, skybase,  skybase,  ROT90,  "Omori Electric Co., Ltd.", "Sky Base", GAME_SUPPORTS_SAVE )
 
 /* extra ROMs, protection, and sound hardware replaced with AY8910 */
-GAME( 1981, jumpbug,  0,        jumpbug,  jumpbug,  jumpbug,  ROT90,  "Sega (Rock-Ola license)", "Jump Bug", GAME_SUPPORTS_SAVE )
-GAME( 1981, jumpbugb, jumpbug,  jumpbug,  jumpbug,  jumpbug,  ROT90,  "bootleg", "Jump Bug (bootleg)", GAME_SUPPORTS_SAVE )
+GAME( 1981, jumpbug,  0,        jumpbug,  jumpbug,  jumpbug,  ROT90,  "Hoei (Rock-Ola license)", "Jump Bug", GAME_SUPPORTS_SAVE ) // or by Alpha Denshi Co. under contract from Hoei?
+GAME( 1981, jumpbugb, jumpbug,  jumpbug,  jumpbug,  jumpbug,  ROT90,  "bootleg (Sega)", "Jump Bug (bootleg)", GAME_SUPPORTS_SAVE ) // bootleg or licensed?
 GAME( 1983, levers,   0,        jumpbug,  levers,   jumpbug,  ROT90,  "Rock-Ola", "Levers", GAME_SUPPORTS_SAVE )
 
 /* 2nd CPU driving AY8910 for sound */
diff --git a/src/mame/drivers/laserbas.c b/src/mame/drivers/laserbas.c
index 20244e27d6d..61b421a22d5 100644
--- a/src/mame/drivers/laserbas.c
+++ b/src/mame/drivers/laserbas.c
@@ -283,6 +283,6 @@ ROM_START( futflash )
 	ROM_LOAD( "ff.8",         0xf000, 0x0800, CRC(623f558f) SHA1(be6c6565df658555f21c43a8c2459cf399794a84) )
 ROM_END
 
-GAME( 1981, laserbas, 0,        laserbas, laserbas, 0, ROT270, "Amstar / Hoei", "Laser Base (set 1)", GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
-GAME( 1981, laserbasa,laserbas, laserbas, laserbas, 0, ROT270, "Amstar / Hoei", "Laser Base (set 2)", GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
-GAME( 1981, futflash, laserbas, laserbas, laserbas, 0, ROT270, "Hoei",          "Future Flash",       GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
+GAME( 1981, laserbas, 0,        laserbas, laserbas, 0, ROT270, "Hoei (Amstar license)", "Laser Base (set 1)", GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
+GAME( 1981, laserbasa,laserbas, laserbas, laserbas, 0, ROT270, "Hoei (Amstar license)", "Laser Base (set 2)", GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
+GAME( 1981, futflash, laserbas, laserbas, laserbas, 0, ROT270, "Hoei", "Future Flash", GAME_NO_SOUND | GAME_NOT_WORKING | GAME_SUPPORTS_SAVE )
diff --git a/src/mame/drivers/spacefb.c b/src/mame/drivers/spacefb.c
index 45e7f48ae87..8998c2ad898 100644
--- a/src/mame/drivers/spacefb.c
+++ b/src/mame/drivers/spacefb.c
@@ -501,6 +501,6 @@ ROM_END
 
 GAME( 1980, spacefb,  0,       spacefb, spacefb,  0, ROT270, "Nintendo", "Space Firebird (Nintendo)", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
 GAME( 1980, spacefbg, spacefb, spacefb, spacefb,  0, ROT270, "Nintendo (Gremlin license)", "Space Firebird (Gremlin)", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
-GAME( 1980, spacebrd, spacefb, spacefb, spacefb,  0, ROT270, "bootleg", "Space Bird (bootleg)", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
+GAME( 1980, spacebrd, spacefb, spacefb, spacefb,  0, ROT270, "bootleg (Karateco)", "Space Bird (bootleg)", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
 GAME( 1980, spacefbb, spacefb, spacefb, spacefb,  0, ROT270, "bootleg", "Space Firebird (bootleg)", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
 GAME( 1980, spacedem, spacefb, spacefb, spacedem, 0, ROT270, "Nintendo (Fortrek license)", "Space Demon", GAME_IMPERFECT_COLORS | GAME_IMPERFECT_SOUND )
diff --git a/src/mame/drivers/williams.c b/src/mame/drivers/williams.c
index e696ef0f4b7..f9bcc0ee050 100644
--- a/src/mame/drivers/williams.c
+++ b/src/mame/drivers/williams.c
@@ -2899,9 +2899,9 @@ GAME( 1980, zero2,      defender, defender,            defender, defndjeu, ROT0,
 GAME( 1980, defcmnd,    defender, defender,            defender, defender, ROT0,   "bootleg", "Defense Command", GAME_SUPPORTS_SAVE )
 GAME( 1981, defence,    defender, defender,            defender, defender, ROT0,   "bootleg (Outer Limits)", "Defence Command", GAME_SUPPORTS_SAVE )
 GAME( 1981, startrkd,   defender, defender,            defender, defender, ROT0,   "bootleg", "Star Trek (Defender bootleg)", GAME_SUPPORTS_SAVE )
-GAME( 1980, mayday,     0,        defender,            mayday,   mayday,   ROT0,   "<unknown>", "Mayday (set 1)", GAME_SUPPORTS_SAVE )
-GAME( 1980, maydaya,    mayday,   defender,            mayday,   mayday,   ROT0,   "<unknown>", "Mayday (set 2)", GAME_SUPPORTS_SAVE )
-GAME( 1980, maydayb,    mayday,   defender,            mayday,   mayday,   ROT0,   "<unknown>", "Mayday (set 3)", GAME_SUPPORTS_SAVE )
+GAME( 1980, mayday,     0,        defender,            mayday,   mayday,   ROT0,   "Hoei", "Mayday (set 1)", GAME_SUPPORTS_SAVE ) // original by Hoei, which one of these 3 sets is bootleg/licensed/original is unknown
+GAME( 1980, maydaya,    mayday,   defender,            mayday,   mayday,   ROT0,   "Hoei", "Mayday (set 2)", GAME_SUPPORTS_SAVE )
+GAME( 1980, maydayb,    mayday,   defender,            mayday,   mayday,   ROT0,   "Hoei", "Mayday (set 3)", GAME_SUPPORTS_SAVE )
 GAME( 1981, colony7,    0,        defender,            colony7,  defender, ROT270, "Taito", "Colony 7 (set 1)", GAME_SUPPORTS_SAVE )
 GAME( 1981, colony7a,   colony7,  defender,            colony7,  defender, ROT270, "Taito", "Colony 7 (set 2)", GAME_SUPPORTS_SAVE )
 GAME( 1982, jin,        0,        jin,                 jin,      defender, ROT90,  "Falcon", "Jin", GAME_SUPPORTS_SAVE )