“Mockingbirds don’t do one thing but make music for us to enjoy. They don’t eat up people’s gardens, don’t nest in corncribs, they don’t do one thing but sing their hearts out for us. That’s why it’s a sin to kill a mockingbird.”

Even after 59 years, “To Kill a Mockingbird” has lessons to teach.

Harper Lee’s iconic novel of race and coming of age in fictional 1936 Maycomb, Alabama, has not gone out of print since it was first published in 1960. More than 40 million copies later, the Pulitzer Prize winner remains a staple of middle school and high school classrooms, valued by educators for its depiction of class and racial prejudice, and by parents for extolling the virtues of standing for honor and principle against all odds.

“To Kill a Mockingbird,” unfortunately, is also big business these days, and it offers a modern lesson on the effects of casual, unthinking greed.

A new version of the story hit Broadway late last year. Updated for the Trump era by screenwriter Aaron Sorkin of “West Wing” fame, it has become a critical and commercial triumph.

That success was apparently not enough for the play’s producers, who were determined to make Sorkin’s version of Mockingbird the only game in town -- any town.

Dozens of community and nonprofit theaters across the country were forced to abandon their own productions of the play, lest they face a costly, $150,000-a-performance legal challenge from the producers of the Broadway version. Those small-town stagings were all licensed by the Dramatic Publishing Company, which owns the amateur rights to a version written by Christopher Sergel. A provision in their 1969 agreement states that no performance can be staged within 25 miles of a major city if there is an ongoing Broadway show licensed by Lee’s estate.

Marblehead’s Mugford Street Players got caught in the dispute, the amateur troupe forced at the last minute -- and after six weeks of rehearsals -- to abandon plans to stage Sergel’s version of the play. The Marblehead Little Theatre, unfortunately, is a few narrow streets too close to Boston, invoking the “major city” rule. Meanwhile, a production in nearby Hamilton was allowed to go on because it was a stage length outside the 25-mile limit.

“The rationale is that we damage the marketability of the Broadway production with our production,” Mugford Street’s John Fogle told reporter Paul Leighton. “It’s really kind of ridiculous.”

Those on Broadway, where premium seats are going for $325, seem to care little for how the controversy is playing in the sticks, where tickets cost about $20. Let’s also remember there is currently no Boston staging of the Sorkin play in the offing.

“We hate to ask anybody to cancel any production of a play anywhere, but the productions in question as licensed by DPC infringe on rights licensed to us by Harper Lee directly,” said Scott Rudin, producer of the Sorkin version. “The Sergel play can contractually continue to be performed under set guidelines as described in detail in its own agreement with Harper Lee — and as long as those guidelines are adhered to, we have no issue with the play having a long life.”

Gee, thanks.

Let’s pause for a bit to take in the silliness of the situation: A big-budget Broadway show, with a cast featuring Emmy winner Jeff Daniels as Atticus Finch, is somehow financially threatened by a small-town, shoestring production hundreds of miles away, its Scout a multi-tasking 14-year-old rehearsing after classes at Salem High School and before nightly rounds of homework. 

“If a theater was consciously stealing creative license, that would be one thing,” said Chris Peterson, founder of the OnStage blog. “This is something else entirely. This is wrong. Prohibiting others to perform this piece goes against everything the novel is about in the first place.”

Fortunately, the show will go on for the Mugford Street Players. The Gloucester Stage Company, safely outside the 25-mile zone, has offered its beautiful oceanside theater for the Marblehead production.

There is a reason Lee’s novel survives in the American imagination to this day. The author made it plain herself in a letter written in 1966: “To Kill a Mockingbird,” she wrote, “spells out in words of seldom more than two syllables a code of honor and conduct.”

It’s a lesson that is sadly lost on those who would squash the chance for Americans everywhere to see those sentiments come to life on the stage, be it on Broadway or in Marblehead.

For tickets to the Mugford Street Player’s Gloucester shows, which begin March 29, visit gloucesterstage.com