As bitcoin, ethereum and other cryptocurrencies get increasing attention from investors, Wall Street and its traditional banks continue to adjust to the shift. Catch up on this week's top stories highlighting the intersection of these old guard and new school areas of finance with this recap compiled by The Fly.

1. CFTC SUBPOENAS EXCHANGES: The Commodity Futures Trading Commission has subpoenaed several bitcoin exchanges for comprehensive trading data to assist an investigation over whether manipulation has distorted prices in markets linked to cryptocurrencies, the Wall Street Journal reported Friday. CME Group (CME), which launched bitcoin futures in December and derived their final value from prices at exchanges Bitstamp, Coinbase, itBit and Kraken, had asked the exchanges to share reams of trading data, but they declined saying the demand was intrusive. The CFTC was frustrated CME didn't have in place agreements that would compel bitcoin markets to share data tied to the contracts and subpoenaed the exchanges.

2. SEC SAYS ETHER TRADES NOT SECURITIES TRANSACTIONS: William Hinman, the SEC's director, division of corporation finance, said Thursday, "'Can a digital asset that was originally offered in a securities offering ever be later sold in a manner that does not constitute an offering of a security?' In cases where the digital asset represents a set of rights that gives the holder a financial interest in an enterprise, the answer is likely 'no.' In these cases, calling the transaction an initial coin offering, or 'ICO,' or a sale of a 'token,' will not take it out of the purview of the U.S. securities laws. But what about cases where there is no longer any central enterprise being invested in or where the digital asset is sold only to be used to purchase a good or service available through the network on which it was created? I believe in these cases the answer is a qualified 'yes.'...And putting aside the fundraising that accompanied the creation of Ether, based on my understanding of the present state of Ether, the Ethereum network and its decentralized structure, current offers and sales of Ether are not securities transactions."

3. S. KOREAN CRYPTO EXCHANGE HACKED: South Korean cryptocurrency exchange Coinrail lost over $40M in altcoins belonging to users following an apparent hack, TechCrunch reported. The hackers took $19.5M-worth of NPXS tokens issued by payment project Pundi X's ICO, $13.8M from Aston X, an ICO project focused on decentralizing documents, $5.8M in tokens for Dent, a mobile data ICO, and over $1.1M Tron, a project originating from China.

4. WELLS FARGO BANS CRYPTO CREDIT CARD PURCHASES: Wells Fargo (WFC) has banned cryptocurrency purchase on its credit cards as it "will continue to evaluate the issue as the market evolves," Bloomberg reported Monday. The bank joins Citigroup (C), JPMorgan (JPM) and Bank of America (BAC), which limited cryptocurrency purchases on credit cards in February citing market volatility and credit risks.

5. BANKS UNLIKELY TO USE DISTRIBUTED LEDGERS FOR NOW: Banks are unlikely to use distributed ledgers to process cross-border payments currently due to scalability and privacy issues, Reuters reported Friday. Several banks have tested or deployed xCurrent, a system Ripple developed for international payments that uses "bi-directional messaging" and can eventually plug into distributed ledgers, however the technology itself "is not a distributed ledger."

CRYPTO STOCK PLAYS: Cryptocurrency revenues have been pointed to as reasons to be bullish on Advanced Micro Devices (AMD) and Nvidia (NVDA) in select research. Overstock (OSTK), DPW Holdings (DPW), Kodak (KODK), Seven Stars Cloud (SSC), Riot Blockchain (RIOT), Pareteum (TEUM) and Social Reality (SRAX) are other stocks that have been touted, or promoted themselves, as a way to play the crypto theme.

PRICE ACTION: As of time of writing, bitcoin dropped about 14.2% this week to $6,513 in U.S. dollars, according to CoinDesk.