Signed and Sealed in Blood

On August 31, 2012, the band announced the album's title and first single, "Rose Tattoo" through their Facebook page. The title of the album is taken from lyrics in "Rose Tattoo". The band asked fans to tattoo themselves with the new logo from the album's cover and send photos and videos to their web site by September 19, 2012. The images were used in the packaging for the CD and vinyl album.

The album has sold 106,000 copies as of Sept. 10, 2013.

Where "Going Out in Style" told the story of a fictional character named Cornelius Larkin—complete with an obituary written by Michael Patrick MacDonald for the liner notes -- "Signed..." has no such constraints. "This is just the opposite of that," bassist Ken Casey explains, "just us having fun and making the most catchy, singalong kind of songs we can. It's not that the last album wasn't fun. It was. 'Going Out in Style' is one of the records I'm most proud of, of anything we've done. But it gave me a couple migraines along the way, getting through that because everything was so connected. This time we cut loose." But he does feel that "Signed..." is also "almost a continuation of ('Going Out in Style'), in a musical sense. There's an upbeat, party vibe to it. A lot of these songs, we were having such a good time writing them and just enjoying the writing process. It's the quickest we've released an album, ever, after another."

The group has been previewing some of the new songs during its Halfway To St. Patrick's Day U.S. tour, which wraps up September 21, 2012 in Boston. Casey describes the final track, "End of the Night," as "the closing time, kind of loser's anthem, about people who don't want to go home." The album also features a holiday song called "The Seasons Upon Us," which Casey promises "is definitely not some cheesy Christmas tune. It's about a dysfunctional family."

Professional ratings

Aggregate scores
Source	Rating
Metacritic	77/100[7]
Review scores
Source	Rating
AllMusic	[8]
The A.V. Club	B+[9]
The Boston Globe	(favorable)[10]
Consequence of Sound	C+[11]
Kerrang!	[7]
Los Angeles Times	[12]
musicOMH	[13]
PopMatters	[14]
Rolling Stone	[15]
Sputnikmusic	3.6/5[16]

Signed and Sealed in Blood was well received by music critics. The album holds an average critic score of 77/100 at Metacritic, based on 17 critics, indicating "generally favorable reviews".[7] Gregory Heaney of AllMusic gave the album four out of five stars called it "an album that's sure to please Murphys fans both old and new".[8] At The Observer, Hermione Hoby gave the album two stars out of five, criticising it as 'hearty but slightly absurd'.[17]

Fans who pre-ordered the album through the band's website received MP3 download of the song, "The Season's Upon Us" as well as a digital download card with their order which included three exclusive songs. "The Season's Upon Us" was also released as a 7" single in special colors of red, green and white with the non-album b-side "AK-47 (All I Want For Christmas Is An)".[18]

Dropkick Murphys

• Al Barr – lead vocals
• Tim Brennan – guitars, accordion, bouzouki, piano, whistle, vocals
• Ken Casey – lead vocals, bass guitar
• Jeff DaRosa – banjo, bouzouki, mandolin, mandola, acoustic guitar, piano, autoharp, vocals
• Matt Kelly – drums, vocals
• James Lynch – guitars, vocals
• Scruffy Wallace – bagpipes, whistles

Additional musicians

• Winston Marshall - guest banjo on "Rose Tattoo"
• Michelle DaRosa - vocals on "Rose Tattoo" and "The Season's Upon Us"
• Parkington Sisters - strings on various songs, vocals on "End of the Night" and "Shark Attack"
• Niki Cremmen - vocals on "Rose Tattoo"
• So Many Close Friends - additional gang vocals on various songs