Global disinflation is a hot topic for bond investors. In the day-to-day life of markets, though, one form of inflation is proving sticky: in the order books for new issues.

The bond market has recently seen some spectacular deals and spectacular order books. Verizon Communications demolished the record for a corporate-bond issue in September, selling $49 billion of debt and garnering orders of $100 billion. Spain drew orders in January of €40 billion ($55.25 billion) for a €10 billion 10-year bond. Last week, Greece saw €20 billion demand for its €3 billion offer.

Curiously, the day after pricing, the Greek bond's yield rose to above 5.1% from 4.95%—hardly expected for a hot deal. The bond traded back above its issue price Thursday. But the apparent mismatch between supply and demand of new bonds speaks to fundamental shifts in the market—and risks for investors.

Regulators are paying much closer attention to bond-market plumbing. But the issue isn't as simple as investors recklessly inflating orders or banks accepting them blindly.

Regulations such as Basel III, designed to make banking safer, look to be making the secondary market for bonds less liquid. Difficulty buying bonds in the secondary market may encourage investors to ramp up bids for new issues.

Banks managing bond sales face a tricky balancing act. Issuers often want bonds sold to long-term holders. Banks are likely to want to reward customers who trade with them or big investors placing anchor orders. But they have reasons to avoid accepting inflated orders: Investors who receive more bonds than they want will likely seek to dump them.

For trickier borrowers, the composition of the order book may be as much of an issue as its size. Around 33% of the new Greek issue was placed with hedge funds. But to ensure liquidity for a new issue, at least some of it needs to go to short-term investors.

Ultimately, pricing and allocation of a new bond issue is more art than science. That is doubly so in a world where the net supply of bonds has fallen sharply, thanks to banks deleveraging and central banks scooping up debt.

As long as too much money is chasing too few securities, order inflation looks set to continue.