Why does Rolls Royce have 4 separate tickers, on OTC Markets?

I'll start with RYCEY and leave RLLCF for last.

• RYCEY — This is an American Depositary Receipt (ADR). In the US, 5-letter tickers that end with "Y" are ADRs. This is a sponsored ADR. According to the Rolls Royce investors FAQ:

  Which Stock Exchange is the Company listed on?

  The Company is listed on the London Stock Exchange. The Company's ticker symbol is RR. Rolls-Royce Ordinary Shares are also traded "over the counter" in the United States in the form of a sponsored American Depositary Receipt (ADR) facility with J.P. Morgan as the depositary. Each ADR represents one Ordinary Share.

  You can get more information about this ADR from J.P. Morgan's website: https://adr.com/drprofile/775781206. On that web page, you will be able to see the historical dividends and ADR fees.

  The maximum fees are mentioned in the "deposit agreement" in the Form F-6 filing available in EDGAR. The fees can be found in Exhibit A, section 7 "Charges of Depositary".

• RYCEF — This is an "F share" (the 5-letter ticker ends with "F"). US broker-dealers created this ticker to provide US investors with quotes of Rolls Royce in US dollars instead of British Pounds. This represents US over-the-counter market quotes of Rolls Royce's London Stock Exchange shares. More details about F shares: FAQ on F Shares - OTC Markets

• RYCRF — According to FINRA's OTC Daily List, this is "ROLLS-ROYCE HOLDINGS PLC, LONDON ORD GBP0.2 NPD 11 11 20 Rights 11/11/2020" (screenshot). It was added on 30 October 2020, and removed on 11 November 2020. It is no longer traded.

  It was an F share that represented a rights issue that closed on 11 November 2020. Information about this rights issue from London Stock Exchange's Regulatory News Service (RNS):

  • Proposed Recapitalisation (dated: 1 October 2020)
  • Publication of a Prospectus (dated 1 October 2020)
  • Result of Rights Issue (dated 12 November 2020)

• RLLCF — This is an F share representing Rolls Royce's "C Shares". According to the 2019 shareholder guide:

  What are C Shares?

  C Share are non-cumulative redeemable preference shares of 0.1p each in the capital of Rolls-Royce that can, during defined periods, be redeemed for cash. Rolls-Royce will generally issue C Shares to all ordinary shareholders twice a year in lieu of a cash dividend. C Shares should not be confused with your Ordinary Shares.

  Note that there has recently been some changes to C Shares, so the quote above is probably outdated. Refer to Payments to shareholders — C Share issues for updated information about the C Shares. I don't know where/when the change was first announced, but I found a mention of the change in a press release dated 27 August 2020 (see section "Payments to shareholders" on page 50).