Last fall, a brokerage firm serving both RIAs and investor clients moved to drop commissions, setting off a flurry of similar moves.

Two months later, Charles Schwab and TD Ameritrade made headlines with news that they’d reached an agreement to merge in a $26 billion deal that includes some 10,000-plus RIAs and over $5 trillion in total assets.

This development came two years after TD Ameritrade bought Scottrade for $4 billion, absorbing $170 billion in retail client assets.

While the blockbuster deal raises questions for advisors, “the biggest concern [of advisors] should be the threat to their [own value] proposition because of pricing, branding and service challenges” in a more consolidated and competitive field, financial blogger Michael Kitces said when the merger was announced.

For more details on the transaction, check out the timeline below: