The opinion of the court was delivered by: Levy, United States Magistrate Judge
On June 6, 2003, plaintiffs Fredy Amaya ("Amaya") and Samuel Estrada ("Estrada"), landscape and construction laborers, brought this action to recover unpaid wages. They amended their complaint on September 15, 2003 to add Jose Alvarado ("Alvarado"), Jose Garcia ("Garcia"), Paul Lopes ("Lopes"), Thomas Baez ("Baez"), Luis Campos ("Campos"), and Leoladio Acosta ("Acosta"), additional laborers, as plaintiffs.*fn1 (Amended Complaint, dated Sept. 15, 2003 ("Am. Compl."), ¶ 5.) Plaintiffs allege that defendants Garden City Irrigation, Inc. ("GCI"), Garden City Maintenance., Inc. ("GCM") (together, "employer defendants"), Michael Moonan ("Moonan"),*fn2 Donna Milcetic ("Milcetic"),*fn3 First National Insurance Company of America ("First Nat'l"), and other unknown entities (collectively, but excluding First Nat'l, "defendants") did not pay them proper compensation for the work they performed for employer defendants from 1997 to 2003. (Am. Compl. ¶ 1.) Plaintiffs seek to recover money damages for unpaid minimum wage, overtime and "prevailing wage" compensation, and liquidated damages and reasonable attorney's fees pursuant to the Fair Labor Standards Act of 1938 ("FLSA"), as amended, 29 U.S.C. § 201, et seq., New York State Labor Law, and the common law. (Am. Compl. ¶ 1.) They also seek redress for retaliation and retaliatory termination of employment pursuant to 29 U.S.C. § 215 and N.Y. Lab. § 215. (Am. Compl. ¶ 1.)
Plaintiffs now move pursuant to Federal Rule of Civil Procedure 15(a)(2) and (c) and Section 16(b) of the FLSA to add Jose Hernandez ("Hernandez"), Jose Garcia ("Garcia"), and Pedro Gil ("Gil") (collectively, "opt-in plaintiffs") as named plaintiffs in this action and to have opt-in plaintiffs' claims relate back to the original complaint. Plaintiffs also move pursuant to Rule 21 to add third-party defendant/fourth-party plaintiff Adam Tedesco ("Tedesco"), once part-owner of employer defendants, as a named defendant with regard to the New York State law claims of Lopes, Alvarado, and Estrada and to have their claims against him relate back to December 31, 2007. (Plaintiffs' Reply Memorandum in Opposition of Plaintiffs' Motion to Amend the Complaint ("Pls. Reply") 7, 9.) Defendants do not contest plaintiffs' motion except as it relates to Tedesco. For the reasons stated below, plaintiffs' motions are granted.
Leave to amend a complaint pursuant to Rule 15 of the Federal Rules of Civil Procedure "falls within the sound discretion of the court." Andujar v. Rogowski, 113 F.R.D. 151, 154 (S.D.N.Y. 1986) (citing Zenith Radio Corp. v. Hazeltine Research, Inc., 401 U.S. 321, 330 (1971)). Rule 15(a)(2) provides that "a party may amend its pleading . . . with . . . the court's leave. The court should freely give leave when justice so requires." Fed. R. Civ. P. 15(a)(2). Generally, courts look favorably upon amendments, "as they tend 'to facilitate a proper decision on the merits.'" Sokolski v. Trans Union Corp., 178 F.R.D. 393, 396 (E.D.N.Y. 1998) (quoting Junior Gallery, Ltd. v. Neptune Orient Line, Ltd., No. 94 Civ. 4518, 1997 WL 26293, at *2 (S.D.N.Y. Jan. 22, 1997)); accord Andujar, 113 F.R.D. at 154. "'If the [movant] has at least colorable grounds for relief, justice . . . require[s]' that the court grant leave to amend a complaint." Soloski, 178 F.R.D. at 396 (quoting Golden Trade, S.r.L. v. Jordache, 143 F.R.D. 504, 506 (S.D.N.Y. 1992)) (brackets & ellipses in original). The only reasons a court may deny a motion for leave to amend are "undue delay, bad faith, prejudice to the opposing party or the futility of the amendment."*fn4 Andujar, 113 F.R.D. at 154; accord Monahan v. N.Y.C. Dep't of Corr., 214 F.3d 275, 283 (2d Cir. 2000); Manley v. Mazzuca, No. 01 Civ. 5178, 2007 WL 4233013, at *3 (S.D.N.Y. Nov. 30, 2007) (citing Dluhos v. Floating & Abandoned Vessel, Known as "New York", 162 F.3d 63, 69 (2d Cir. 1998)); see Block v. First Blood Assocs., 988 F.2d 344, 350 (2d Cir. 1993); Vysovsky v. Glassman, No. 01 Civ. 2531, 2007 WL 3130562, at *3 (S.D.N.Y. Oct. 23, 2007); Soloski, 178 F.R.D. at 396.
B. The Relating Back Doctrine
When granting leave to amend a complaint, Rule 15(c)*fn5 permits the court to deem an otherwise time-barred action timely based on the "relation back" doctrine. See Soloski, 178 F.R.D. at 397.
For an amendment adding a new plaintiff or federal claim to relate back to the original complaint, "the amendment must relate to the same conduct, transaction or occurrence described in the original complaint and [the] defendant must have had the requisite notice of the original action." Andujar, 113 F.R.D. at 154; accord Soloski, 178 F.R.D. at 397. Such notice may be formal or informal. Andujar, 113 F.R.D. at 154-55 (citing Fed. R. Civ. P. 15(c) Advisory Committee Note of 1966). These two factors ensure that Rule 15(c) amendments satisfy the dictates of due process, which require that a party "have . . . proper notice of the claim contained in the amendment prior to the running of the statute of limitations." Id. at 155. If a defendant "is fully apprised of a claim arising from specific conduct and has prepared to defend the actions against him, he will not be prejudiced by the addition of a new plaintiff." Id.; see Soloski, 178 F.R.D.at 398 (holding that amendment will relate back "when the status of the original plaintiff and a liberal reading of the complaint apprise defendant of the existence of the additional plaintiff's existence and claims" or "if the defendant has had actual notice that additional parties might assert claims arising out of the transaction or occurrence at issue") (quoting Andujar, 113 F.R.D. at 158) (quotation marks omitted).
To determine whether amendments that add state law claims to a complaint relate back, the court must turn to the relevant state law, in this case that of New York. Fed. R. Civ. P. 15(c)(1)(A) (stating that claim may relate back when "the law that provides the applicable statute of limitations allows relation back"); see also Murphy v. West, 533 F. Supp. 2d 312, 316 (W.D.N.Y. 2008) ("The general rule is that if state law 'affords a more forgiving principle of relation back than the one provided in this rule, it should be available to save the claim.'") (quoting DeRienzo v. Harvard Indus., Inc., 357 F.3d 348, 353 n.8 (3d Cir. 2004) (quoting Advisory Committee's Note to 1991 Amendment of Fed. R. Civ. P. 15)); Laureano v. Goord, No. 06 Civ. 7845, 2007 WL 2826649, at *5 (S.D.N.Y. Aug. 31, 2007); Blakeslee v. Royal Ins. Co., No. 93 Civ. 1633, 1998 WL 209623, at *3 (S.D.N.Y. Apr. 29, 1998). New York's relation back doctrine permits a plaintiff to amend a complaint and add new claims, plaintiffs, or defendants "even though, at the time of the amendment, the statute of limitations has expired." Beck. v. Consol. Rail Corp., 394 F. Supp. 2d 632, 640 (S.D.N.Y. 2005) (citing N.Y. C.P.L.R. § 203); see Buran v. Coupal, 661 N.E.2d 978, 981 (N.Y. 1995). A party invoking the doctrine must establish that (1) both claims arose out of the same conduct, transaction or occurrence; (2) the new party is 'united in interest' with the original party such that she can be charged with notice of the original action and will not be prejudiced in maintaining a defense on the merits; and (3) the new party should have known that, but for a mistake as to the proper party, the action would have been brought against her as well.
Beck, 394 F. Supp. 2d at 640 (citations omitted); accord Buran, 661 N.E.2d at 981. The first prong of the test mirrors its federal counterpart as discussed above. See, e.g., Fed. R. Civ. P. 15(c)(1)(B); Andujar, 113 F.R.D. at 154; Soloski, 178 F.R.D. at 397. For the second prong, the court will find a party "united in interest" with another where the interest of the parties in the subject-matter is such that they stand or fall together and that judgment against one will similarly ...