Two specific kinds of corporate tax breaks, the size of which officials can’t even estimate yet, are at the center of bargaining between the Kansas House and Senate that threatens to push the Legislature right up to its deadline Friday night.

Those tax breaks are part of an effort by lawmakers to return to the taxpayers any unanticipated “windfall” the state could see as a side effect of the federal tax cuts that President Donald Trump and the Republican-controlled Congress pushed through. But they involve areas of tax law that most ordinary people have never heard of.

One is known by a rather unfortunate-sounding acronym when it’s pronounced out loud: GILTI — Global Intangible Low-Taxed Income. Another involves what’s called “deferred foreign income.”

In essence, both involve the “repatriation” back into the United States of profits and assets held overseas by multinational corporations and their shareholders, something the new federal tax law tries to encourage because under the old law there was a huge tax incentive to keep corporate assets abroad to avoid paying U.S. taxes.

The concern among some lawmakers is that the state of Kansas has received little or no tax revenue from that source in the past because corporations weren’t repatriating those assets. But now, under the new law, they might. And if they do, some of it might be repatriated to Kansas. So the feeling, at least on the Senate side, has been that the state shouldn’t tax that income at all, to prevent the state from reaping a windfall.

That, however, was not the Senate’s original position. Some might remember the melodrama that occurred the night of April 7, the final day of the regular session, when Republicans in the Senate engaged in a lengthy filibuster in apparent hopes of pre-empting a vote on the school finance bill. These items were part of the tax bill that they debated for hours on end, except that the bill they debated at the time called for applying state taxes to 20 percent of that income, not a total exemption.

In conference committee negotiations, however, the Senate recently changed its position to exempting that income entirely from state taxes. And Sen. Caryn Tyson, R-Parker, who leads the Senate negotiating team, even called that part of a “strong Senate position” Wednesday. (The original bill that included a tax on 20 percent passed, 24-16.)

House negotiators haven’t been as willing to go along, in part because nobody has any idea how much potential revenue the state would be leaving on the table. Rep. Steven Johnson, R-Assaria, who leads the House negotiating team, made a counter-offer Wednesday to exempt the GILTI income for one year, tax year 2018, and see how things go from there.

The House also offered to exempt repatriated foreign income, but asked for a provision that said those filers could not repatriate their foreign expenses, because that could be used to reduce other taxes they might owe to Kansas.

Mind you, these are just two parts of a massive tax bill that lawmakers are considering in the final days of the session. There are no fewer than a baker’s dozen other moving parts, some of which are related to the federal tax changes, but many of which are not.

One that is not related to the federal law would be a 25 percent increase in the standard deduction that taxpayers can take if they don’t itemize their deductions, something the House has so far refused to consider because of its estimated $55-$65 million annual price tag.

There is even a provision being discussed to exempt the purchase of gold bullion from state sales taxes.

Recent negotiating meetings have been particularly tense as the clock ticks down to 11:59 Friday night, at which point the session will come to a close. Tuesday night, Sen. Tyson offered what she called a “global package” of 15 items the Senate wanted to put into a single bill — essentially a kind of “take-it-or-leave-it” proposition. The House came back Wednesday morning to reject that offer and made a counter-offer that did not include many of the things the Senate was insisting on.

“This is quite discouraging that the House is willing to risk losing the federal tax cuts for our taxpayers because the time is so short,” Tyson said in a remark that some found ironic, since she was among the Republicans filibustering on April 7, threatening to end the session without passage of either a tax bill or school finance bill. It was also seen as ironic since it was the decision of the Senate, not the House, to set the date for “sine die” adjournment of the session on May 4.

Tyson is also seeking the Republican nomination for the 2nd District congressional seat in the upcoming August primaries.

Johnson, however, was not swayed and replied in his characteristic understated tone: “I recognize strong Senate positions, and I don’t mean to discount that. But there may also be strong House positions. And that’s the challenge that we have to figure out how to come together on.”

The two Democrats on the conference committee, Sen. Tom Holland, of Baldwin City, and Rep. Tom Sawyer, of Wichita, have been relatively quiet during the talks because Democrats don’t want to consider tax cuts before they know whether the Kansas Supreme Court will accept the Legislature’s latest school finance package.

In addition, they have said, the state has only seen vague and, some argue, unreliable estimates about how much of a so-called “windfall” the state stands to receive as a result of federal tax law changes.

“So I think we’re being very foolhardy trying to move forward and make policy based upon those anticipated changes from the Trump tax cuts. We really haven’t seen them in effect yet,” Holland said in an interview.

The conference committee was scheduled to continue meeting Wednesday night in hopes of reaching a deal that can pass both chambers.