Hard-to-trace "ghost corporations" are making large donations to super PACs allied with the 2016 candidates.

The latest batch of campaign finance reports filed Sunday with the Federal Election Commission reveal more money from opaque corporations flowing to super PACs.

As we reported last week, this election cycle has seen a proliferation of "ghost corporations" making major contributions to big-money groups, including some entities that were formed just days or weeks before donating. Three groups -- End Citizens United PAC, Democracy 21 and the Campaign Legal Center -- filed FEC complaints Tuesday about one of the pop-up companies, Children of Israel LLC. It was incorporated in California last year by a Cupertino real estate agent who listed "donations" as Children of Israel's type of business. The limited-liability corporation went on to dole out $400,000 to super PACs supporting former Arkansas governor Mike Huckabee, who has since dropped out of the Republican primary race, and Sen. Ted Cruz (R-Tex).

It remains to be seen whether the FEC's deeply divided six-member panel will take up the complaints. In the meantime, other new mystery donations are cropping up:

Raemar Crest, LLC      

Like many of the low-profile corporate donors we're seeing, Raemar Crest was formed in Delaware, which requires companies to disclose little about their operations. The LLC was set up in 2011 by an incorporation services company. On Feb. 29, it gave $10,000 to Priorities USA Action, a super PAC backing Democratic presidential front-runner Hillary Clinton.

KHSE LLC        

KHSE was also incorporated in Delaware, back in 2007. It donated $10,000 on Feb. 16 to the pro-Cruz Stand for Truth super PAC, listing as its address a stretch of wooded area in Fairfax Station, Va. However, the address does not exist in Fairfax County property records. The entity previously gave $25,000 in 2014 to Unlocking Potential PAC, which was headed by former Hewlett Packard chief executive Carly Fiorina. It also donated $2,500 to the gubernatorial bid of former Virginia attorney general Ken Cuccinelli.

K3 Development LLC

This company gave $25,000 to the pro-Cruz Keep the Promise PAC last June and another $25,000 to the super PAC last month. It lists as its address a large office building in Andover, Mass., but the company does not show up in Massachusetts or Delaware corporate records.

NKSFB LLC

This is the corporate name of Nigro Karlin Segal Feldstein & Bolno, a Los Angeles-based business management firm that specializes "in the representation of high net worth and high income individuals, actors, writers, directors, producers, recording artists, athletes, executives, and other allied professionals in the entertainment industry," according to its website. On Feb. 10, the company contributed $100,000 to New Day for America, a super PAC aligned with Ohio Gov. John Kasich (R). The firm did not return a call for comment on whether the donation was made on behalf of one of its clients.

Decor Services, LLC

This pop-up company was incorporated in Delaware by a paralegal in a Milwaukee law firm in January, two weeks before donating $250,000 to a super PAC backing New Jersey Gov. Chris Christie (R). In February, the LLC shelled out another $250,000 to Conservative Solutions, a super PAC allied with Sen. Marco Rubio (R-Fla.). Christie and Rubio have since dropped out of the GOP presidential primary race.

Anu Narayanswamy contributed to this report.